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Library 
of the 

University of Toronto 








THE AQUARIUM 

ITS INHABITANTS, STRUCTURE, 
AND MANAGEMENT 


Digitized by the Internet Archive 
in 2018 with funding from 
University of Toronto 


https://archive.org/details/aquariumitsinhab00tayl_1 


THE AQUARIUM 

ITS INHABITANTS, STRUCTURE, 
AND MANAGEMENT 


J. E. TAYLOR, Ph.D., F.L.S., F.G.S., Etc. 

AUTHOR OF “HALF-HOURS AT THE SEA9IDE,” “HALF-HOURS IN THE 
GREEN LANES,” “FLOWERS: TIIEIR ORIGIN, SHAPES,” ETC., 
“NATURE’S BTE-PATHS, ' ETC. 


NEW EDITION 


EDINBURGH: JOHN GRANT 
31 GEORGE IV. BRIDGE 
1910 


PRINTED BY OLIVER AND BOYD, EDINBURGH 


PREFACE 


We regard the institution of public aquaria as more 
or less the result of the deeper interest now felt in 
the life-histories of aquatic animals, consequent upon 
that extensive knowledge of natural history which 
is one of the intellectual features of our time. We 
believe their extension will be greater, on this 
account, than those people imagine who hold they 
will share the fate of “ spelling bees,” &c. That 
they are a popular means of education none will 
deny, and the success they have everywhere met 
with leads us to hope they are serving a good 
purpose. 

This little volume is intended as a handbook or 
popular manual to our public aquaria, so as to render 
them still more effective as a means of education. 
Their history, construction, and principles of manage¬ 
ment have been briefly described, as also the natural 
history of the chief animals which have been more or 
less successfully acclimatised. The list of the latter 
is constantly being extended, and there appears no 


VI 


PREFACE 


limit to the number which may be healthily main¬ 
tained and exhibited. 

We have had the great advantage of having the 
following pages overlooked by Mr. W. A. Lloyd, of 
the Crystal Palace, to whom our best thanks are due 
for many valuable suggestions. 

The work is now presented to the public in the 
hope that it may add to the educational effects of 
our public aquaria, and be the means of rendering 
the education in zoology more popular and exten¬ 


sive. 


CONTENTS. 


CHAPTER I. 

THE HISTORY OF AQUARIA, 

Works of P. H. Gosse — The ‘Origin of Species’ — Fish sup- 
plies — Royal Commission on Fisheries — Ova of cod and 
whiting, how deposited — Discovery in Brighton Aquarium 
— Saville-Kent on history of common herring— Dr. Gunther 
on “ whitebait ” — Professor Sars on cod ova — Mr. Lloyd on 
herring culture — Herring in Manchester Aquarium — Young 
of crawfish (. Phyllosoma ) — Hamburg Aquarium — Growth 
of salmon — Mr. Jackson on salmon-trout — Ancient fish¬ 
ponds — Roman piscina — Red mullet — Cost of Roman fish¬ 
ponds — Chinese fish-culture — Mediaeval fish-culture — An¬ 
tiquity of the pike — Fish-food of the thirteenth century — 
The edible frog — The common frog — The life-scheme of 
our globe .Page i 


CHAPTER II. 

history of aquaria — continued. 

Priestley’s discovery of oxygen — Trembley and his Hydras — 
Sir John Daly ell — The Bordeaux Aquarium — Dr. Daubeny 
on plants and animals — Dr. N. B. Ward’s experiments on 
aquaria — Dr. Johnston’s zoophytes — Mrs. Anna Thynne — 
Mr. R. Warington’s experiments on aquaria — Mr. Gosse’s 
ditto — Works of Mr. Gosse — Aquaria at Surrey Zoological 
Gardens and Dublin ditto — Dr. Ball’s contrivance for 




CONTENTS. 


aeration — Mr. Gosse’s artificial sea-salts — Hanover and 
Berlin Aquaria — Aquaria in British and continental towns 

— Havre Aquarium — Aquarium of the French Acclimatisa¬ 
tion Society— Naturalists at British aquaria — The Crystal 
Palace Aquarium — History and structure of ditto — Ditto of 
Brighton Aquarium — Dr. Dohrn’s aquarium at Naples — 
Professor Agassiz’s aquarium at Penekese Island — The 
Manchester Aquarium— : Southport ditto — Yarmouth ditto 

— Westminster ditto — Aquaria in course of erection Page io 


CHAPTER III. 

PRINCIPLES OF THE AQUARIUM. 

Pleasures and educational influence of aquarium keeping — 
Cruelty to animals — Streamless aquaria — Relation of 
animal to vegetable life — Balance of ditto — Parasitic fungi 
on aquarium animals — Lloyd’s contributions to literature 
of aquaria—Over-stocking aquaria—How to proceed in 
stocking an aquarium — Bell-glasses and their uses — De¬ 
velopment of green algae in aquaria — How to arrest ditto — 
How to keep down ditto — Temperature of ditto — Water in 
aquaria not to be changed — Aquarium fountain — Aquatic 
plants — Structure of cheap fountain — Evaporation of water 
in aquaria — Dust in ditto — How to remove it • • • • 24 


CHAPTER IV. 

CONSTRUCTION OF FRESH-WATER AQUARIA. 

Where materials can be purchased — Details of cheap aquarium 
— Bell-glasses — Dr. Lankester’s 1 Aquavivarium ’ — Flower- 
stand with bell-glass aquarium — Oblong tank for window 
aquaria — Polygonal tanks — Cement for joining sides of 
tanks — Rockwork of tanks — Materials for rockwork — 
Fresh-water plants for tanks — Duckweeds — Mud and sand 
for fresh-water aquaria — Deodorisation of aquaria — How 
to prepare aquatic plants for aquaria — Stock animals for 


CONTENTS. 


IX 


ditto — How to remove decaying objects from ditto— How 
to feed aquatic animals — Best food for ditto — How aquaria 
get wrong — Means of putting aquaria right — “ Conva¬ 
lescent ” glass — Best plants for ditto — Circulating fresh¬ 
water aquaria — How to keep aquaria perpetually healthy 

Page 36 

CHAPTER V. 

AMPHIBIANS AND FISHES OF THE FRESH-WATER 

AQUARIUM. 

Over-stocking aquaria —Yellow-spotted salamanders — Mexican 
Axolotl — Great water newt — Superstitions regarding ditto 
— Male and female of ditto — Smooth newt — Habits of 
ditto — Habits of great warty newt — Tadpoles of smooth 
newt — Development of ditto—Food of ditto — Straight¬ 
lipped warty newt — Palmated smooth newt — Spawn of 
frogs and toads — Goldfishes and their food — Three-spined 
sticklebacks — Nest-building habits of ditto — Rough-tailed 
stickleback—Miller’s thumb — The loach — Food of loach 
and gudgeon — The minnow — The “ pope ” — Common 
perch — Common and Prussian carp — The bleak — Scales 
of ditto — Roach and dace — The “ rudd ” — The pike — 
Dr. Lankester on ditto — Silurus glanis — Introduction of 
ditto in English rivers — Ganoid fishes — The bony pike — 
Acclimatisation of foreign fishes .50 

CHAPTER VI. 

THE AQUATIC GARDEN AND ITS PLANTS. 

Circulatory system of aerating large aquaria—Mr. Kent on 
fungoid growth upon fishes — Probable cause of ditto — 
Selection of aquatic plants for ornamental purposes — The 
mare’s tail — Canadian weed ( Anacharis )— Vallisneria — 
Flowers of ditto — Water lilies — Water plantain — Arrow¬ 
head — Flowering rush — Forget-me-not — Water mint — 



X 


CONTENTS. 


Brook lime — Water violet — Speedwell — Buck-bean — 
Flowers of ditto — Aquatic Polygonum — Water crowfoot 
— Dimorphous leaves of ditto — Water frog-bit — Water 
soldier — Abundance of ditto in eastern counties — Bladder- 
wort — Leaves of ditto — Villarsia and Trapa — Pond 
weeds — Star-worts — Horn-wort — Water milfoil — Sweet 
flag — Bur-reed — Beauty of aquatic gardens • • Page 71 

CHAPTER VII. 

MOLLLUSCA, INSECTS, ETC., OF THE FRESH-WATER 

AQUARIUM,. 

Bryant’s “ Thanatopsis ” — Stock of aquaria — Battles in ditto 
— Mollusca of ditto — Limnea stagnalis — L. auricularia — 
Habits of these two species — Limneapereger — Planorbis 
corneus — Geological antiquity of fresh-water shells — Plan - 
dina vivipara — Habits of ditto — Bythnia , Pisidium, and 
Sphcerium — Use of ditto in aquaria — Swan mussel — Unios 
— Aquatic insects — Life-histories of ditto — Metamorphoses 
of ditto — Dragon-flies, larvae of — Larva of Dyticus — Fero¬ 
cious character of ditto — Dyticus marginalis , male and 
female — Habits of ditto — Great aquatic beetle ( Hydro - 
philus) ; its habits — Wriggling beetles — Water bugs — 
Water scorpions — Water boatmen — Various species of 
caddis-worms —- Development of ditto — Larvae of Ephemerce 
— Water spiders and ticks—Nest of water spider — Care 
required in selection of aquatic insects, &c. • • • • • • 97 

CHAPTER VIII. 

THE AQUARIUM AS A NURSERY FOR THE MICROSCOPE. 

Interest of aquarium objects — Microscopic life— Desmids and 
diatoms — Unicellular character of ditto — Hyalotheca , 
Euastrum , Cosmarium , Closterium , and other desmids — 
Nature and habits of desmids —- Structure of desmids and 
diatoms — Frustules of diatoms — Their siliceous character 



CONTENTS . 


xi 


— How to prepare them for microscopical mounting — 
Beauty of diatom frustules — Utilisation of ditto in the arts 

— Various species of diatoms, Isthmia , Pinnularia, Pleicro- 
sigma , Navicula, Stauroneis, Cocconeis, &c. — Stalked 
diatoms, as Licomophora — Structure of latter — The Amcebas 

— Fresh-water sponges — Structure of ditto — Hydras — 
Their habits and development—Rotifers — Sessile rotifers 

— Melicerta and Stephanoceros — Their habits and structure 

— Infusoria — Vorticella , Epistylis , &c. — Rotifer vulgaris 

— Habits of ditto — Fresh-water polyzoa — Lophopus 

crystallina, Plumatella repens , &c. — Cyclops , its habits 
and development — Water fleas — Relation of animalcules 
to each other . Page 113 


1 ■ 

CHAPTER IX. 

MARINE AQUARIA FOR ROOMS. 

Difficulties attending private marine aquaria — Construction of 
ditto — Rockwork for ditto — Polygonal marine table tanks 

— Sea-weeds for ditto — Sea-lettuce ( Ulva ) — Cladophora — 
Oxygen-yielding qualities of certain sea-weeds — Calli- 
thamnion — Green and red sea-weeds — Delesseria and 
Plocamium — Cladophora , Bryopsis, Griffithsia , Ceramium , 
Rhodymenia, Padina , Corallina officinalis , &c. — Small 
wrack — “ Irish moss ” — Fructification of sea-weeds — Zoo¬ 
spores of ditto — Their use as food for lowly organised 
animals — Best time for introducing sea-weeds into aquaria 

— Spontaneous appearance of sea-weeds in tanks of public 

aquaria—Oxygenation of sea water — Artificial oxygen — 
Marine scavengers, as Haliotis , Patella, &c. — Mr. W. R. 
Hughes on construction of marine tanks — Dark-chambered 
slope-backed tanks — Aeration of tanks — Contrivances for 
ditto — Regulation of light and temperature of ditto — 
Evaporation of water — Artificial sea-salts, their chemical 
composition — Mr. Gosse on ditto — Specific gravity balls 
and hydrometers — Self-acting air-can for preserving aquatic 
animals . 139 




CONTENTS, 


• • 
Xtl 


CHAPTER X. 

OUR PUBLIC AQUARIA. 

Establishment of large public aquaria—Mr. Lloyd’s part in 
developing ditto — The Crystal Palace Aquarium — Ditto at 
London and Dublin Zoological Gardens — Show tanks in 
public aquaria — Circulation and aeration of sea water in 
ditto — Barnum’s white whales — Hurwood’s contrivance for 
aerating large aquaria — Application of ditto in Hamburg 
Aquarium — Mr. Lloyd’s method of large underground 
reservoirs — Saville-Kent on ditto — Crystal Palace and 
Brighton methods of circulation in aquaria — Relative 
merits of ditto — Capacity of tanks in Crystal Palace, West¬ 
minster, Brighton, Great Yarmouth, Manchester, and South- 
port Aquaria — Details of sizes of tanks, &c., in ditto — 
Food-tanks of our public aquaria— Cost of food for animals 
in ditto—Food of animals in ditto—Nocturnal habits of 
herrings and dog-fishes — Saville-Kent on ditto — How 
marine animals are fed — Organic matter in sea water 

Page 161 


CHAPTER XI. 

MAMMALIA, REPTILIA, AND FISHES OF PUBLIC MARINE 

AQUARIA. 

Lung-breathing aquatic animals — Grampuses at Brighton 
Aquarium — Porpoises at ditto — “ Sea-lions ” at ditto — 
Alligators and crocodiles at Southport, Manchester, and 
Brighton — Edible turtles at Brighton—Hawk’s-bill turtle 

— Marine fishes — The lancelet ( Amphioxus ) at Sydenham 

— Mud-fish at Brighton — Smooth hound and tope — 
Common dog-fish — Its habits — Small-spotted dog-fish — 
Eggs of skate and dog-fish — Mode of reproduction in sharks 
and rays — Thornback — Angel fish — Homelyn ray — 
Common skate — Sharp-nosed ray — Cat-fish — Teeth of 


CONTENTS. 


Xlll 

ditto — Smooth blenny — Secretions of fishes —Parasites of 
ditto — Beauty of the blennies — Butterfly blenny —• Vivi¬ 
parous blenny — Young of ditto — Tameness of the blennies 
— Rock goby — Structure of sucking disk of ditto — Spotted 
goby — Heterogeneous character of “ whitebait.” Page 175 


CHAPTER XII. 

FISHES FOR MARINE AQUARIA. 

Attractive marine fishes — The wrasses — Ballan wrasse —■ 
Structure of mouth of wrasses — Male and female wrasses — 
Their difference in colour — Habits of wrasses — Red wrasse 
— Food of wrasses — Young of wrasse— Cuckoo wrasse — 
Corkwing and rainbow wrasses — The dragonet — Difference 
between male and female of ditto — Angler fish — Modi¬ 
fication of dorsal fin-rays of ditto — Lump sucker — Struc¬ 
ture of sucking disk — Young of lump sucker — Fifteen- 
spined stickleback — The pogge — The gurnards, their 
colours — Butterfly gurnards — Modification of rays of pec¬ 
toral fins of gurnards — Streaked gurnard — Grey gurnard —• 
The piper — Lesser weever — Sting rays of weevers — Dr. 
Gunther on ditto — The basse.192 


CHAPTER XIII. 

FISHES FOR THE MARINE AQUARIUM. 

Migratory fishes in aquaria — Mackerel in Brighton Aquarium 

— Herrings in ditto — The pilchard — Whiting and cod — 
Ova of cod — Spawning of cod at Brighton and Sydenham 

— Food of cod — Three-bearded Rockling — Five-bearded 
ditto — Haddock— Coal-fish— Grey mullet — Food of ditto 

— Sea-bream — The sturgeon and sterlet — Pipe-fishes, their 
habits and structures—Different species of pipe-fishes— 
Breeding of ditto — Sea-horses {Hippocampi) — Their struc¬ 
ture, habits, and food— Breeding of ditto at Manchester and 
Southport — Flat-fishes — Their embryology — Adaptation 



XIV 


CONTENTS. 


of colour to sea-bed — Structural modifications of flat-fishes 
— The plaice, sole, and turbot — Difference in coloured 
sides of ditto — Modification of eyes of ditto — The brill, 
dab, halibut, turbot, &c. — Conger-eel, John dory, and guard 
fish — Mud-fishes — Modern study of fish • • Page 209 

CHAPTER XIV. 

CUTTLE-FISH, MOLLUSCA, ETC., OF MARINE AQUARIA. 

Victor Hugo’s octopus — Mr. Henry Lee on the octopus — Huge 
octopuses or cuttle-fish — Fishermen’s stories of ditto — The 
common octopus — Structure of ditto—Habits and food of 
ditto— Common sepia— Internal bone of ditto — Its micro¬ 
scopical structure — Common squid— Pen of ditto — Welsh 
octopus — Geological antiquity of cuttle-fishes — Mollusca 
for shallow water-tanks — Limpets, chitons, &c. — Structure 
of chitons — Young of ditto — Key-hole limpet — White 
whelk — Egg-cases of ditto — Red whelk — Venus’ ear, or 
Haliotis — Nassa and Purpura — Vegetable scavengers — 
Natica , Turitella , and Trochus — Shell-less mollusca or sea- 
slugs — Aplysia, Doris , &c. — Bivalve mollusca — Their re¬ 
productive powers — The common mussel Oysters — Their 
usefulness in aquaria — Young of ditto — Food of ditto — 
Life-history of oysters — American clams — Species of 
cockles — Pectens or scallops — Boring mollusca — Sand 
mussels — Wood-boring mollusca — Madras , Tellinas 
Lima , Cyprina , &c. — Ascidians — Young of ditto — Sea- 
mats — Structure of ditto — Botryllus — Clavelina, &c. 228 


CHAPTER XV. 

CRUSTACEA, ECHINODERMS, ANNELIDS, ETC., OF MARINE 

AQUARIA. 

Animals as aquarium scavengers — Hermit crabs — Habits 
and structure of ditto — Battles of ditto for empty shells 
— Spiny lobster, or crawfish — Embryology of ditto — 


CONTENTS. 


xv 


Common lobster — Embryology of ditto — Life-history of 
lobster — Mr. Lloyd on moulting of lobster — Prawns — 
Common shrimp — Habits of shrimps — Banded shrimp 

— “Cup shrimp”— Gammarus and Hippolyte — “Night- 
walker”— Squat lobsters — Shore crab and edible crab — 
Spiny spider-crab — Mr. Lloyd on decoration of certain 
crabs — Miss G. Stephens on ditto — Hyas, Pisa, Inachus, 
&c. — Swimming crabs — Crabs at Sydenham — Masked 
crabs — Northern stone-crab — Nut crabs, &c. — Barnacles 

— Life-history of ditto — Various species of ditto — Barnacles 

at Sydenham — Lepas and Scalpellum — Star-fishes and 
sea-urchins, their structures — Ambulatory apparatus of 
ditto — Habits of ditto — Ur aster, Ophiura , Ophiocoma, 
Solaster , Comatula, &c. — Sea-cucumbers — Annelids or 
sea worms — Various species of ditto — Sea-mouse— Habits 
of sea worms .Page 254 


CHAPTER XVI. 

SEA-ANEMONES AND OTHER ZOOPHYTES, ETC., OF MARINE 

AQUARIA. 

Gosse and Lankester on sea-anemones — Couch’s story of sea- 
anemone — The dahlia wartlet — Plumose anemone — 
Diet of sea-anemones — Orange-disked anemone — Daisy 
anemone —Cave-anemone — Parasitical anemones, Adamsia, 
&c. — Messmateship of Adamsia and hermit crabs — 
Beadlet anemone — The opelet — Corals in aquaria — 
Caryophyllia, Balanophyllia , &c. — Gorgonias or sea-fans 
— Iris , Hippuris , &c. — Structure of Gorgonias — Campanu- 
larians —Larvae of ditto — Oaten-pipe corallines — Sea-firs, 
or Sertulariee — Hydra-tuba — British sponges in marine 
aquaria — Various species of sponges—The marine aquarium 
as a nursery for microscopic animals — Conclusion • • 289 

311 


Index 






THE AQUARIUM. 


CHAPTER I. 

THE HISTORY OF AQUARIA. 

Notwithstanding a good deal of quibbling which 
has taken place respecting the word “ Aquarium/' 
there can be no doubt it has now gained its ground, 
as signifying contrivances for the support of living 
fresh-water and marine animals under such artificial 
conditions as resemble their natural surroundings. 
The word has passed out of the region of philology 
into that of common parlance, and has now become 
stereotyped in dictionaries. 

The charming works of P. H. Gosse undoubtedly 
did much to make aquarium keeping popular about 
twenty-three years ago. Everyone who loved nature 
could not help feeling attracted towards the lovely 
objects, which he showed were so abundant on our 
coast, after his animated descriptions of them. To 
a great extent this was in advance of the natural 
science of the time, and although it was the means 




2 THE HISTORY OF AQUARIA. 

of collecting a great deal of information relative to 
the habits of the invertebrate animals, it had to fall 
back until science came up with it. The enormous 
strides which natural science has made since the pub¬ 
lication of the ‘ Origin of Species ’ have necessitated 
large aquaria, where the new study of the embryology 
and larval conditions of the lower animals could be 
more easily followed. Since that time, also, zoology 
has become more attractive even to general readers. 
The fact that evolutionists and non-evolutionists have 
taken sides over zoological questions, renders it im¬ 
perative that both shall observe more and theorise 
less. It has been found, also, that large aquaria may 
be rendered places of the highest amusement, as well 
as of the easiest and pleasantest instruction. Hence 
their numbers are largely increasing, and we doubt 
not the time is not far distant when all our large 
towns will be provided with them, so that all classes 
may know more of the marvellous works of God. 
To economists, aquaria cannot fail to be of the 
highest interest, for even within the last few years, 
observation at several of them has settled various 
most important facts relating to the life-history of 
some of those creatures which are most valuable to us 
as food. In one instance, at least, it was the means 
of preventing the framing of a law that was based 
on zoological ignorance, and which would have done 
as much harm to our fish supply as it was intended to 
do good ! In 1865 a Royal Commission, on which 


OVA OF CODFISH. 


3 


several naturalists sat, met at some of our fishing 
ports, and took evidence from fishermen and others 
as to whether trawling did not do much harm, by 
breaking up the sea bed where the ova of fish had 
been deposited. The idea then was that the cod and 
whiting—two of the most abundant of our native 
food-fishes — deposited their eggs on the sea floor. 
Professor Sars, the well-known Danish naturalist, had 
expressed his opinion that the ova of these fish floated 
on the surface ; but it was first substantiated in the 
Brighton Aquarium, where it was found that the ova 
both of these fish and the mackerel, floated on the 
surface during the entire period of their development. 
Had it not been for this discovery, it is more than 
likely that by this time the fishing trade, as well as 
the fish supply, would have been crippled by a law 
which would have restrained trawling operations 
over cod grounds during the whole of the spawning 
season. 

Mr. Saville-Kent, at the Manchester Aquarium, 
has contributed towards the history of the common 
herring, from its young state. Dr. Gunther, the well- 
known ichthyologist, had already declared his belief 
that by far the greater part of “ whitebait” consisted 
of the fry of herrings.* If this is so, then, in con¬ 
suming them so recklessly, we are interfering with 
the chief fish-food of the common people. Mr. Lloyd 

* Dr. Gunther affirmed that Clupea alba , or whitebait, was the young 
of Clupea harengus , or the common herring. 

B 2 


4 


THE HISTORY OF AQUARIA . 


(who was the first to keep whitebait in London, in 
1858), and others had experienced a difficulty in 
herring culture. In consequence of the migratory 
habits of these fish they often injured themselves by 
dashing against the glass or the rockwork of the 
tank in which they were kept. As they move about 
principally by night, it struck Mr. Kent to illuminate 
the tank by a feeble light, so that the outlines of the 
walls, rocks, &c., should be visible to the fish. This 
plan succeeded admirably, and by its aid Mr. Kent 
kept and fed whitebait until they have grown to half 
the size of the ordinary herring. At the time he 
made this announcement, the fish were eighteen 
months old.* 

In addition to the above-mentioned important facts 
with which our large aquaria have made us ac¬ 
quainted, there are others not yet worked out, but 
which are in process of careful observation. It was 
discovered in the Hamburg Aquarium that the Phyl- 
losoma , one of the ‘‘glass crabs,” which had been 
placed in a separate order prepared for it, is only the 
young ol tne crawfish (Palinurm qnudricornis). The 
Brighton Aquarium has further contributed impor¬ 
tant information as to the rapidity of the growth of 
the salmon. Before then, the growth of this fish was 
thought to be much slower than observation and ex- 

* Mr. Kent obtained his specimens in a very young state. The only 
person who has hatched out herrings in aquaria is Mr. Stephenson, of 
Brixton, 


RED MULLET . 


5 


periment have proved. At the Southport Aquarium, 
under Mr. C. L. Jackson, experiments are being con¬ 
ducted which will make us better acquainted with the 
life-history of another valuable food-fish, the salmon- 
trout. 

Although artificial contrivances for preserving fish 
alive have undoubtedly been in vogue for many 
centuries, aquaria, in the sense in which we under¬ 
stand the word, are peculiarly modern. The ancient 
Romans paid as great attention to their fish-ponds as 
wealthy gentlemen, of horticultural tastes, now do to 
their orchid and fern houses. No expense seems to 
have been spared in making these fish-ponds as large 
and attractive as possible, or in obtaining valuable and 
beautiful fish for stocking them. Amongst others, the 
red mullet (Mullus barbatus ?) appears to have been 
the greatest favourite. It was kept in the ponds for 
the sake of its beauty, and was usually brought to the 
table alive, so that the assembled guests could indulge 
in the pleasure of witnessing the rapidly changing 
prismatic tints which the fish assumed whilst dying. 
Not unfrequently canals led from the fish-ponds into 
the banqueting hall. The red mullet, when it attained 
a large size, was of great value; one of four pounds 
and a half fetching a sum equal to 60/. sterling. These 
mullets are immortalised by the price that was given 
for them in the reign of Caligula, about 240/. Pliny 
relates that the fish-pond of one of the Roman patri¬ 
cians (C. Herius) was sold for a sum amounting 


6 


THE HISTORY OF AQUARIA . 


to more than 32,000 1 . So extensive were these 
ponds, and so well stocked, that the same gossipy 
naturalist tells us the fish alone from the ponds of 
Lucullus, the well-known gourmand, fetched a sum as 
large as that just named ! The Romans were capital 
judges of another modern delicacy, the oyster, the 
modern demand for which has been run almost as 
high as it was nearly two thousand years ago. Reser¬ 
voirs were constructed for the preservation of oysters, 
and large sums of money were laid out in getting 
stock and taking proper care of them. 

The Chinese have long kept live fish for the table 
and market. Our well-known gold and silver fish 
(Cyprinus auratus ) come from their country, and 
were introduced into Europe as ornamental living 
objects more than two centuries ago. Pepys perhaps 
refers to these in his ‘ Diary/ as a “ fine rarity ; of fishes 
kept in a glass of water, that will live so for ever— 
and finely marked they are, being foreign.” Both the 
Japanese and Chinese have long kept these fish in 
artificial tanks and glasses for amusement, and have 
succeeded in roughly training them. During the 
middle ages, fish-ponds were esteemed a necessary 
appurtenance to monasteries, abbeys, and even halls. 
The long abstinence from all animal food, except fish, 
during Lent, and the many other fasting days imposed 
by the Church, rendered it necessary that fish of some 
sort should be easily available for use. The moats 
which ran round castles or other baronial buildings, 


ANTIQUITY OF PIKE . 


7 


often served the double purpose of defence and fish 
preserves. In the immediate neighbourhood of abbeys 
we usually find large fish-ponds, unless (as is frequently 
the case) these religious buildings stood near some 
well-known stream. No doubt at this time, in spite 
of the difficulty of transit, European fish were more 
or less interchanged, so that it does not do to accept 
their present geographical distribution as a natural 
one. It is all but certain that the carp was brought 
from southern Europe to the more northerly parts ; 
its great size and esteemed flavour rendering it a 
favourite. The pike is said to have been introduced 
into England in like manner, but this is hardly 
likely, as we find its remains in the post-glacial 
river-bed of Mundesley, in Norfolk. Thus we have 
incontestable evidence of the existence in Britain 
of the pike long before the historic period, and 
when the physical geography of the surface was, in 
Norfolk at least, very different from what it is now. 
Tastes, as regards fish and other aquatic animals, 
have differed much since mediaeval times. The 
upper classes regarded pike and tench as fit only for 
the lower orders, whilst they did not scruple to enjoy 
the coarse flesh of the sea dog, the porpoise, and even 
the whale! In an old document of the thirteenth 
century, about fifty kinds of fish are mentioned which 
were retailed in the French markets. Lacroix says 
that a century later, the flesh of the whale was salted 
down for the use of the common people. Congers, 


8 


THE HISTORY OF AQUARIA. 


cuttle-fish, and sturgeon were the principal food-fishes 
of the masses; whilst turbot, sole, and “John Dory” 
had even then obtained, by their high price, the 
aristocratic position of catering only for the stomachs 
of the wealthy. 

The edible frog (Rana esculenta) is another animal 
which has been specially cared for by those who 
have learned to like it as an article of food. Tanks 
or ponds, in which it can pass through its ordi¬ 
nary life-history, and whence it can easily be fished 
out for the table, still exist in France. Of course 
we need not here do more than remark that the 
edible frog is another species than that which is so 
common in England; although there is no reason 
in the world why the latter should not be as dainty 
an article of food, if there were only more of it. Pond 
frogs were regarded as among their choicest morsels 
by the ancient Gauls and Franks, in whose country 
these amphibians have continued to be more or less 
favourites ever since. Formerly they were served at 
the best tables, dressed with a green sauce. 

Between the artificial contrivances for the preser¬ 
vation of aquatic and other animals designed for the 
table, and the modern aquaria in which they are kept 
to administer to the growing love for knowledge, 
there is as great a gulf fixed as there is between the 
mind and the stomach. Very little knowledge indeed 
has been handed down to us from the costly piscinae 
of the ancient Romans, or the more homely fish- 


EDIBLE FROG. 


9 


ponds of mediaeval times. From the lofty eminence 
whence ignorant men looked down, all lowlier creatures 
seemed beneath their study. It remained for the era 
when we had learned to regard all things that God has 
made as worthy of our consideration, to increase our 
knowledge of their “ times and seasons.” We can 
hardly imagine it possible that little more than a 
century ago the “ great Cham ” of English literature 
declared that natural history was a study only fit for 
children ! And we are thankful that we have grown 
to this—to regard the great life-scheme of our planet, 
past and present, including objects as minute as 
others are huge, and as structurally simple as others 
are complex, as one in its nature, evolved through the 
omniscience of an All-wise Being! If nothing less 
than Omnipotence could have produced it, surely we 
cannot but esteem it one of the noblest studies in 
which the human mind can be engaged. Science is 
one with the Psalmist in regarding the inorganic and 
organic kingdoms of nature as doing His will—beasts 
and all cattle, worms and feathered fowls, mountains 
and hills, fruitful trees and all cedars, fire and haiJ, 
snow and vapour and stoimy wind fulfil His word ! 


10 


THE HISTORY OF AQUARIA. 


CHAPTER II. 

THE HISTORY OF AQUARIA — continued. 

The most natural of all the artificial conditions under 
which fish were kept in readiness for the table were 
the old fish-ponds. Many of the latter were covered 
with the usual aquatic vegetation, which thus kept the 
water pure ; or else a stream regularly passed through 
the lattice-work at either end. The relation which 
plants and animals bear to each other was not fully 
known even half a century ago. It required con¬ 
siderable progress in chemistry before the gases 
which they gave off were understood. Unquestionably 
the first step in this direction was made by Dr. 
Priestley, of Birmingham, who observed that oxygen 
gas was given off by plants when under the active 
stimulancy of sunlight. Aquatic animals had been 
described by Trembley, Baker, Leuwenhoek, Hooke, 
and others; but they either obtained them direct, or 
else, as Trembley did his Hydras , kept them in jars 
by constantly changing the water. Naturalists were 
not aware of the needlessness of their labour until a 
long period afterwards. Even Sir John Dalyell, whose 
minute investigations into the structures and habits o*" 
zoophytes were published in his splendidly illustrated 


ORIGINAL AQUARIA. 


II 


work on ‘The Powers of the Creator displayed in 
the Creation,’ and in his ‘ Rare and Remarkable 
Animals of Scotland,’ and who kept many of the 
animals alive whilst he was observing on or experi¬ 
menting with them, did so by constantly changing 
the sea water in which they were kept. One of the 
most wonderful things in a modern aquarium, to a 
person ignorant of natural history, is that the sea and 
fresh water never want changing. Such people have 
not yet learned that the dry land of the entire globe 
is only one huge vivarium , and that the Atlantic and 
Pacific oceans, as well as all rivers and lakes, are 
likewise only immense natural aquaria. This well¬ 
being of terrestial and aquatic plants and animals is 
kept up and perpetuated without changing either the 
air or water. What naturalists strive after is, to re¬ 
present these natural conditions as much as possible. 

One of the first notices we have of the establish¬ 
ment of aquaria on the modern basis of adjusting 
animal and vegetable life, is that of Bordeaux, com¬ 
menced by M. de Moulins, in 1830. This naturalist 
found that by keeping plants in the water where his 
fish and mollusca were, the latter were stronger and 
healthier for it. But the question shortly afterwards 
assumed a thoroughly scientific foundation, although 
the cautious way in which conclusions which now 
seem to us self-evident, were approached, may appear 
ludicrous. They were accepted, however, in the true 
spirit of scientific research, which ought not to take 


12 


THE HISTORY OF AQUARIA . 


anything for granted that has not been amply proved. 
At the meeting of the British Association at Cam¬ 
bridge, in 1833, Dr. Daubeny showed that plants 
when in water (and aquatic species particularly) gave 
out oxygen and absorbed carbon under the influence 
of light. After detailing his experiments he expressed 
his opinion—an opinion which has since then not only 
been proved true, but which is universally accepted— 
that “ he saw no reason to doubt that the influence of 
the vegetable might serve as a complete compensation 
for that of the animal kingdom.” An old proverb 
says : “A child on a giant’s shoulders sees farther than 
the giant.” It is only the superficial who smile at 
the strenuous efforts of great intellects to attain unto 
a knowledge of those principles which we now regard 
as self-evident and incapable of contradiction. There 
is an evolution of knowledge as there is of animal 
and vegetable life. Daubeny saw dimly less than 
half a century ago what every teacher in physical 
geography now imparts to his class—that the oxygen 
generated in the virgin forests of the Amazons valley 
may be brought by the wind to bring health to 
the fetid streets and alleys of crowded European 
cities, and that in return the carbonic acid breathed 
forth from our over-populated towns may be carried 
on the “ wings of the wind,” to be eventually absorbed 
by the incalculable stomata which crowd the under 
surfaces of the leaves in the same forest-clad region ! 

The labours of an unassuming but true naturalist, 


JOHNSTON'S EXPERIMENTS. 


13 


Dr. N. B. Ward, did much towards proving to students 
of nature that the magnificent views of Priestley, 
Daubeny, and others were both true and capable of 
being practically applied. Mr. Ward, in 1842, pub¬ 
lished a little work which gave a series of experiments 
showing that animals and plants might be kept in air¬ 
tight glass cases, and that each might be so adjusted 
as to breathe in what the other breathed out. He had 
commenced this study in 1829, and the celebrated 
“Wardian cases” for ferns, now to be seen in most 
drawing rooms, are the popular results. Dr. John¬ 
ston, the well-known writer on ‘ British Zoophytes/ 
adopted the above-mentioned compensatory principle 
in 1842, at which time he had a store of sponges, 
zoophytes, &c., in course of artificial preservation for 
scientific purposes. These animals were kept in small 
vessels wherein had been placed the common Coral- 
lina, the sea lettuce ( Ulva), and several others; and 
the result was so successful that he suggested the 
possibility of marine aquaria on a more extended 
scale.* 

The knowledge thus gained by a few experiments 
was destined shortly to receive considerable accre¬ 
tions. In 1850, Mr. R. Warington (whose name is 
inseparably associated with the history of aquaria) 
made a communication to the Chemical Society on 

* The first attempt to keep the sea water constantly fresh by the 
presence of living seaweeds was successfully carried out by Mrs. Anna 
T'nynne, in 1846, 


14 


THE HISTORY OF AQUARIA. 


his own experience in keeping a fresh-water aqua¬ 
rium. It was of a very simple and unpretending 
character, and differed little from that to which Pepys 
refers in his ‘ Diary/ consisting merely of a glass globe 
of fresh water in which two goldfishes had been 
placed, together with some plants of Valisneria. The 
latter is one of the best oxygen-producers of all 
known aquatic plants, and has long been a favourite 
with aquarium keepers. By-and-by, Mr. Warington 
introduced some pond snails to eat away the green 
algae which formed along the inner surface of the 
glass. Two years afterwards, he and Mr. Gosse ex¬ 
perimented after a similar fashion with sea water. 
This was the commencement of that rage for small 
marine aquaria which shortly afterwards set in. Tanks 
were constructed for the purpose, and marine animals 
and plants introduced in such proportions as were 
hoped to neutralise each other’s respiration. 

The most marked epoch in the history of the 
marine aquarium, however, undoubtedly took place 
when Mr. Philip Henry Gosse’s most charming books 
made their appearance. Their attractive style of 
description of the lovely objects which are to be 
found in the commonest rock-pools of our coasts, 
and which it is possible to preserve to constantly 
delight the eye, induced hundreds of people to com¬ 
mence aquarium keeping. Never before had the 
common objects of the seaside found a historian at 
once so charming and so accurate. And although, 


GOSSES EXPERIMENTS . 


15 


after a time, a great many people took to some other 
new “hobby,” and allowed their aquaria to fall into 
neglect, sufficient enthusiasm was created to keep up 
the practice to the present time. Some of our public 
museums, notably that of Liverpool, shortly after¬ 
wards exhibited small tanks or glass vessels, con¬ 
taining aquatic animals and plants so arranged as to 
keep up an equilibrium. Mr. Gosse first began with 
sea anemones, the easiest of all marine objects to 
obtain and afterwards to keep in healthy order. A 
collection of these, and of some scarcely less attractive 
sea worms which he had made at Ilfracombe, were 
purchased by the Zoological Society of London, and 
transferred to the new fish-house which had just been 
built in the Zoological Gardens. In making a further 
collection for the aquarium which was opened there 
in 1853, Mr. Gosse gathered most of the material that 
shortly afterwards appeared in his work on the ‘ Ma¬ 
rine Aquarium ’ and ‘ Rambles of a Naturalist on the 
Devonshire Coasts.’ The small aquarium opened in 
the Zoological Gardens, London, in 1853, was the first 
public one started in England, and, although it has 
long been superseded, it has done good work. In the 
same year another public aquarium was opened for a 
short time at the Surrey Zoological Gardens. That at 
Dublin, which commenced about the same time, was 
more long-lived, and was remarkable for the ingenious 
way in which the curator, Dr. Ball, supplied the tanks 
with fresh air. He so constructed air-bellows that 


l6 THE HISTORY OF AQUARIA . 

the visiters to the aquarium worked them with their 
hands, as a sort of amusement in the intervals of 
pacing about examining the tanks, and the Doctor 
found the air supply thus administered was sufficient. 
It is, however, too uncertain a method for other 
institutions to copy. 

In fitting up small marine aquaria, the chief 
difficulty which people found who lived inland was 
in getting good sea-water. To meet this want, in 
1854, Mr. Gosse showed how artificial sea-water could 
be manufactured, by simply adding salts to pure fresh 
water. The now largely used artificial sea-baths are 
produced by a small modification of Mr. Gosse’s 
recipe. So successful was the experiment that even 
great public marine aquaria, like those soon after¬ 
wards founded at Hanover and Berlin, were supplied 
with salt water manufactured after Gosse’s fashion. 
As soon as it was found that no great labour was 
needed to keep marine and fresh-water animals alive 
and healthy, in simply aerating the water, or in having 
properly adjusted aquatic plants, public aquaria were 
commenced in many of the large towns in Europe. 
Although these were not of the pretentious character 
with which we have now learned to associate the 
name, they did much to develop an interest in na¬ 
tural history. Before long there were aquaria at 
Belfast, Galway, Edinburgh, Scarborough, Yarmouth, 
Boston, Vienna, Hamburg, Cologne, and especially at 
Havre. Some of them consisted of only one huge 


FOREIGN AQUARIA. 


1 7 


tank, wherein the animals obtained fresh air either by 
pumping it in, or by the natural aeration of plants. 
If the tanks were large, however, it was found that 
the latter system was attended with a good deal of 
difficulty. Hence the large tanks were usually aerated 
by causing the water to circulate and be injected in 
sprays, or else jets of air were forced into the water, 
which thus came into contact with oxygen, at the 
same time giving up its carbonic acid. The interior 
of the large tank in the Havre Aquarium was fitted 
up with rockwork, so as to resemble Fingal’s Cave, 
in Stafifa. Similar devices, all of them in bad taste, 
have been adopted at the Brussels, Hanover, Boulogne, 
Berlin, and Cologne aquaria. 

The first of those large public aquaria, which have 
lately grown to such colossal proportions, was that 
opened by the French Acclimatisation Society, in the 
Bois de Boulogne, in 1861. Its length is 150 feet, 
and it is fitted up with fourteen tanks, each of which 
contains two hundred gallons of water. Ten tanks 
are devoted to fresh-water objects, and four to marine. 
The aquarium at Hamburg, opened in 1864, has also 
been very successful. It has long been considered 
one of the best on the Continent; much of its 
success depending upon the fact that Mr. William 
A. Lloyd was the deviser, and for some time the 
curator. Under his able management the zoological 
department attracted a good deal of attention among 
naturalists. In Great Britain we have hitherto been 


c 


18 THE HISTORY OF AQUARIA . 

very fortunate in having men who are well known as 
naturalists at the head of our large aquaria. Thus 
Mr. Henry Lee has charge of that at Brighton. Mr. 
W. Saville-Kent was for some time curator of the 
Manchester Aquarium ; afterwards he partly super¬ 
intended the erection of one at Yarmouth, and later 
was naturalist to the extensive aquarium recently 
built at Westminster. Mr. W. A. Lloyd had charge 
of the well-known Crystal Palace Aquarium since its 
opening in 1871 ; whilst at Southport there is a 
careful and diligent naturalist superintending the 
aquarium in Mr. C. L. Jackson. 

We may regard the establishment of the Crystal 
Palace Aquarium as an important epoch in the history 
of the great public aquaria in this country. That at 
Brighton came into existence subsequently ; although 
the Bill for it had been long obtained ; and the fact that 
the latter paid a good dividend (always an important 
one) was sufficient to induce companies to start those 
at Manchester, Southport, Yarmouth, and elsewhere. 
The size of the Crystal Palace Aquarium is 400 feet 
long by 70 feet broad, whilst the frontage of the tanks 
amounts to 390 feet. There are sixty large tanks 
exhibited, besides those held as reserve. These con¬ 
tain 20,000 gallons of sea water, whilst there is a 
large storage reservoir which holds 100,000 gallons 
more. The largest of these tanks is 20 feet in length, 
and holds 4000 gallons of sea water. The animals 
within the large tanks are viewed through the glass 


THE BRIGHTON AQUARIUM,. 


19 


fronts. There are two adjacent rooms, however, 
in which stand twenty other tanks, varying in 
capacity from 40 to 270 gallons, where the animals 
are viewed from above, looking down into the water, 
as well as laterally. The number of fish, zoophytes, 
annelides, &c., kept alive in this splendid aquarium 
is very great, the sea anemones alone amounting to 
several thousand. Every one of the latter has to 
be fed separately by means of wooden forceps. 

The Brighton Aquarium is the largest yet con¬ 
structed in England, and its interior is perhaps the 
most ornately fitted up, and varied with natural 
objects. The chief corridor (that which contains the 
aquarium proper) extends 220 feet. The tanks are 
placed on each side. They are of various sizes, the 
largest being more than 100 feet long by 40 feet in 
width, and holds 110,000 gallons of sea water, 
or nearly as much as that of all the tanks and 
storage reservoir, included, of the Crystal Palace 
Aquarium. Indeed, this huge tank is big enough for 
the evolutions of porpoises, full - grown sturgeons, 
sharks, sea-lions, turtles, and other large marine 
animals. The next largest tank is 50 feet long by 
30 feet broad. This is placed immediately opposite 
the former. The total quantity of sea water con¬ 
tained in all the Brighton tanks is over 300,000 
gallons, besides which there are storage reservoirs 
into which the salt water is pumped directly from the 
sea outside, which are capable of holding half a million 


20 the history of aquaria. 

gallons more. The salt water thus obtained, how¬ 
ever, is liable to be very turbid. This huge quantity 
takes about ten hours to be pumped in. In the chief 
corridor above mentioned the number of tanks is 
twenty-one. The total frontage of all is about 740 
feet. Octagonal table tanks are also exhibited, in 
which the rarer marine zoophytes, &c., are kept, 
and where the process of fish-hatching may be seen 
going on. 

The most important event which has taken place 
in the history of aquaria, from a purely scientific 
point of view, was undoubtedly the founding of the 
aquarium at Naples by Dr. Dohrn, a German 
naturalist, Mr. Lloyd aiding in its construction. The 
expense was borne almost entirely by himself and 
a few personal friends, but the result has been 
scientifically successful. Dr. Dohrn’s idea was to 
make it a kind of zoological station for the ob¬ 
servation of the life-histories of marine animals 
analogous to astronomical observatories or stations. 
The ground floor of the building covers 8000 feet, 
there being a story above fitted up as a zoological 
dissecting room and laboratory, for the use of natu¬ 
ralists. Further, Dr. Dohrn here receives students 
of natural science, the animals examined being ob¬ 
tained by dredging expeditions which are carried on 
from time to time. A certain number of students’ 
“tables” were offered to various Government scientific 
societies at a fixed sum. Some of these were taken 


NAPLES AQUARIUM. 


21 


by the Universities of Oxford and Cambridge for the 
use of students who might gain the right of stud)*. 
The aquarium is fitted up with the usual tanks, &c., 
on the ground floor, and is opened to the public at a 
certain charge. The money thus received is applied 
towards defraying the expenses of the institution. 
Already some highly important natural history work 
has been done here, notably researches in the em¬ 
bryology of certain fishes. 

Shortly after the Naples station was founded, a 
similar aquarium was commenced at Penekese Island, 
the expense of which was defrayed by the munificent 
act of one of the New York merchant-princes. It was 
placed under the charge of Professor Agassiz, who un¬ 
fortunately died almost before the institution had got 
into working order. The undertaking is now under 
one of the Professor’s sons, and the scientific investi 
gations promised to be of great service to zoology, 
but it has not hitherto proved so successful as was 
expected. There is no reason in the world why all 
our great public aquaria should not prove as effective 
to pure scientific research as they already are to the 
public educationally. Practical students might be 
attached to each, whose time could be devoted to 
zoological research. The time of the curator, how¬ 
ever scientific may be his attainments, must neces¬ 
sarily be too much taken up by the general manage¬ 
ment for him to carry out observations which require 
constant and assiduous watching. 


22 THE HISTORY OF AQUARIA . 

The Manchester Aquarium was the largest inland 
institution of the kind, before that at Westminster 
was built. It was opened to the public in 1874, 
and for a long time was under the direction of 
Mr. Saville-Kent, F. L. S. The main portion of 
the building occupies a superficial rectangular area 
of 150 feet in length, by 72 in breadth. At each 
extremity of the saloon are placed the two largest 
tanks. These occupy the entire width of the room 
40 feet; so that they are capacious enough to con¬ 
tain living animals of considerable size. The total 
number of tanks at present existing is sixty-eight. 
These have a linear frontage of nearly 700 feet, 
which approaches very nearly the total frontage 
of the Brighton tanks. It is contemplated adding 
a series of tanks between the arches separating 
the saloon from the corridors so as to raise the 
total number to one hundred. This would give 
an additional frontage of 224 feet, and so far 
would render the Manchester Aquarium the most 
extensive in this respect. In addition to the above, 
there is a number of octagonal table tanks for fresh 
water and the smaller and rarer marine animals. 

The Southport Aquarium was opened the same 
year as the latter. It is well situated in the town, 
which may be regarded as the “ Brighton ” of the 
Lancashire coast The climate here is milder than 
anywhere in Lancashire, so that it is a place to which 
invalids resort in the winter—hence the “ Winter 


WESTMINSTER AQUARIUM. 


23 


Garden ” which is associated with the aquarium. The 
tanks are constructed much on the same plan as those 
at Brighton, and have a total linear frontage of 500 
feet. Another aquarium at Blackpool, an adjacent 
town on the same coast as Southport, has tanks pos¬ 
sessing a frontage of 250 feet. 

Other aquaria are in course of erection at Scar¬ 
borough, Yarmouth, and elsewhere. That at Yarmouth 
is intended to have show tanks in which 200,000 
gallons of sea water will be held. The building is 
now nearly completed, and is expected to be opened 
to the public during the present year. The exten¬ 
sive aquarium at Westminster is in connection with 
a “ winter garden.” Although opened to the public 
the tanks are not yet fully stocked. The show tanks 
will hold 150,000 gallons of water, whilst there are 
storage reservoirs underneath capable of holding 
600,000 gallons more. Public aquaria are further 
either being built or contemplated at Rhyl, Rothesay, 
Plymouth, Torquay, Southsea, Tynemouth, Mar¬ 
gate, Scarborough, Ipswich, and elsewhere ; and there 
cannot be a doubt that within the next few years, 
most of our large seaside, if not inland, towns will 
possess these useful and attractive institutions. 


24 


PRINCIPLES OF THE AQUARIUM . 


CHAPTER III. 

PRINCIPLES OF THE AQUARIUM. 

THERE can be no question that portable fresh-water 
and marine aquaria may become sources of endless 
amusement and instruction ; and at the same time be 
so constructed as to ornament the rooms in which 
they are placed. Fresh-water aquaria especially, 
may be arranged so as to add to the usual cheerful 
aspect of our English homes. The sight of the moving 
objects, and of the green water-plants covering and 
shooting above the surface of the water is undoubtedly 
cheering. Invalids, or people of sedentary habits, who 
are much confined within doors, might find com¬ 
fort and enjoyment from keeping an aquarium. The 
antics of its little inhabitants, and the little care 
required to keep this miniature world in a healthy 
condition, will draw off their attention from many 
an hour of suffering or care, and unconsciously 
develop a love for God’s creatures. To children, 
aquarium keeping may be the means of imperceptibly 
teaching those feelings of humanity towards the 
lower animals which have hitherto been too much 
neglected. The “ hunting instinct ” is strong in most 


CRUELTY TO ANIMALS . 


25 


boys, and a love of natural history might direct this 
so that it would benefit man and beast alike: not 
unfrequently it assumes the character of unconscious 
cruelty, and the possession of might soon passes into 
the belief that its exertion is right The thoughtless¬ 
ness with which children often torture flies, worms, 
&c., must undoubtedly be the means of partially 
developing a nature that ultimately finds a pleasure- 
in inflicting pain, or in causing death. There is only 
too much truth in the sarcastic remark that when an 
Englishman is on a visit to the country and writes 
home to say he is enjoying himself, you may be sure 
he is killing something! Anything which can neu¬ 
tralise this tendency to cruelty, or develop a more 
tender regard for the lower organised of our fellow 
creatures, becomes a means of moral education. This, 
we contend, might easily be brought about by keeping 
an aquarium, and interesting children in the funny 
ways of its inhabitants. 

Many people think a fresh-water aquarium “only 
gives a lot of trouble, and is always getting out of 
order! ” Of course, there is no denying that both 
these conditions may easily be brought about; but 
cannot the same excuse be made for declining any¬ 
thing else ? An aquarium properly constructed, and 
peopled with proper inhabitants, gives very little 
trouble indeed. A few minutes now and then are 
quite sufficient to keep it in that active, healthy order 
which gives so much pleasure to the possessor. A 


26 


PRINCIPLES OF THE AQUARIUM. 


little common sense exerted in its arrangement cannot 
fail to ensure the perpetual comfort of its inhabitants. 
There are few “ hobbies” which require less trouble, 
and as a rule it will be found that whatever “trouble” 
is caused, is due to ignorance, in not understanding 
the habits of aquatic animals and plants and the con¬ 
ditions under which they best thrive. 

But, it may be asked, how are we to know all about 
such matters, unless we gain experience by first keep¬ 
ing aquaria ? This is very true, but unfortunately 
a great many people do not persevere in keeping 
them, but exchange them for some other amuse¬ 
ment as soon as difficulties arise. Perhaps they have 
not understood the elementary principles on which 
a streamless aquarium should be constructed, and so 
in putting it together wrongly they have been laying 
up for themselves an endless store of trouble. Or 
they have not taken the slightest pains to understand 
whether the animals and plants they have placed in 
the water were likely to agree there. An aquarium 
thus stocked has looked well up to the evening of the 
same day, but next morning it has presented all the 
appearance of a field of battle. In the darkness of 
the night, or rather in the early morning, a dire con¬ 
flict has taken place. Each animal has been battling 
with its fellow, the weakest has gone to the wall, and 
only a few gorged cannibals remain of the too large 
stock with which the aquarium was peopled the day 
before! These are eyeing each other with suspicious 


RESPIRA TION OF PLANTS. 


27 


anger, and it is evident at a glance that the war will 
be waged to the death. 

We cannot too distinctly remember that a stream¬ 
less aquarium is a little world, shut off, as it were, 
from the great world outside. The water, the animals, 
and the plants have to be so adjusted that no extra¬ 
neous addition is required. The marvellous principles 
of adjustment of animal to vegetable life, and con¬ 
trariwise, which holds good all over the surface of the 
globe, is as much in active operation in a portable 
aquarium as on a planet. Under the influence of sun¬ 
light the aquatic plants obtained from some stream or 
pond give off oxygen. You may frequently see it, in 
little bubbles, clinging to the stems and under surfaces 
of the leaves. We need not say that this gas is vitally 
necessary for the support of animal life. Plants there¬ 
fore provide it. On the other hand, it is equally im¬ 
portant that the carbonic acid given out by all animals 
shall be disposed of, or put out of the way so as not 
to injure the creatures that have breathed it, after the 
fashion of the Black Hole at Calcutta. Plants per¬ 
form this function ; and not only do they absorb the 
deleterious gas, but they actually require it for their 
sustenance and growth, as much as animals do the 
oxygen! 

It will be seen, therefore, that in the knowledge of 
this fact we have the means of adjusting a collection 
of aquatic animals and plants, in the vessel we call an 
aquarium, so that there shall be constantly kept up a 


28 


PRINCIPLES OF THE AQUARIUM . 


mutual compensation. The next important thing is 
to know how many animals we can place in a tank 
where there is already a certain number of plants. 
Unfortunately, people who commence keeping aquaria 
are usually too anxious to have as many and as 
varied a stock of animals as possible, and most of 
the evil which overtakes their endeavour arises from 
such over-stocking. It is evident that if there are 
more animals in the aquarium than there are plants 
to provide oxygen for, all of them will have to go 
short. This means universal sickness, and that 
pitiful gasping for air which is often to be seen in 
over-stocked aquaria. Before long it ends in death. 
Perhaps one or two of the weaklier die first. Their 
bodies lie on the bottom and are not removed. De¬ 
composition sets in, and the water becomes fouler 
than ever. A white fungus—or rather the first stage of 
growth in many microscopic fungi—covers the bodies 
of the survivors. The aquarium becomes a painful 
scene of misery, disease, and death—a too vivid 
picture of similar conditions among humanity when 
the latter is horded in fetid and over-populated 
alleys, short of air, short of food, short of fresh, pure 
water! What wonder that many an enthusiastic 
young naturalist has been so thoroughly depressed 
by his first mistake terminating so fatally, that he has 
cast away the contents of his first aquarium, and 
never tried afterwards! 

And yet all this evil has been wrought for want of a 


SICKLY AQUARIA . 


29 


little consideration, and perhaps because people could 
not resist the temptation to have as many animals in 
the aquarium as possible. There is one sure rule of 
guidance to a beginner in these matters—have too 
few animals rather than too many. They will com¬ 
pensate for numbers in the sense of health they seem 
to enjoy, in their vivacious gambols, and sprightly 
habits. The fishes are here, there, and everywhere, 
instead of always gasping with open mouths on the 
surface of the water.* The newts are frolicking about, 
or basking on the surfaces of the leaves and stones. 
Still, although we give this advice, it is to be followed 
with a degree of caution, for the over-stocking of an 
aquarium with plants is liable to overthrow the 
balance of life with almost equally fatal results. If 
there are too many plants the principle of natural 
selection soon sets in ; the weakly or badly adjusted 
species die off; the water becomes foul, and perhaps 
assumes a thick green hue. There is a ready means of 
checking such a disaster, however, for the evil re¬ 
sulting to an aquarium from excess of plant growth is 
not so rapid in its effects as when it is over-crowded 


* Mr. W. A. Lloyd has produced twelve practical articles on Aquaria 
in the following numbers of ‘ Cassell’s Popular Recreator,’ published in 
1873 and 1874:—4, 8, 12, 16, 20, 24, 30, 32, 35, 38, 41, and 45. They 
are illustrated by fourteen woodcuts, of which eight are especially valu¬ 
able as representing, drawn to an accurate scale, how many creatures, 
and of what kinds and sizes, can be maintained in aquaria of a named 
water capacity, of a given water distribution as to surface, and at a 
given temperature. 


30 


PRINCIPLES OF THE AQUARIUM. 


with animals. Moreover, when the first symptoms 
set in you can neutralise them by adding another 
animal—a small fish, a young newt, a few tadpoles, 
or two or three water snails, adding them one by 
one, and waiting to see the results. In this manner 
you proceed as a chemist does when weighing some 
valuable or important medicine. He trickles a little 
at a time until he has attained the exact weight to a 
feather. Excessive growth of plants may be kept 
down in one or two ways. First by modifying the 
light. Owing to the strong desire to see as much as 
possible of what is going on in the aquarium, many 
people expose it as much to the light as they can. 
And, as they have perhaps fallen into the other 
mistake of constructing three, if not four, of the sides 
of glass, it follows that the amount of extra stimulus 
to which the plants are exposed far exceeds that 
which influences them in a state of nature. In a pond 
all the sides are dark—the light can only get into the 
water from above, or through the surface. In a river 
or stream the sides are always dark, and, though the 
light can reach the bottom from behind and in front, 
it passes wholly from overhead. When there is too 
much glass used in the construction of an aquarium 
there is a temptation to use the glass: this means 
exposing the aquarium to light, so that the latter 
passes completely through it on every side. For this 
reason bell-glasses are specially to be shunned for 
fresh-water aquaria. The young beginner has only to 


RESTORATION OF AQUARIA. 


remember that the secret of his successful preservation 
of animals and plants lies in his imitating natural 
conditions as much as possible. And a very slight 
consideration will show him that round bell-glasses, 
and square tanks, having three or four glass sides, are 
as far removed from these as they well can be, unless 
in shady places. 

It is this intensity of light which promotes the 
rapid growth of the greenish film coating the inner 
surfaces of the very glass through which you want to 
watch your animals, as if it were a judgment inflicted 
on your unscientific taste ! This is not the worst of 
it: the same lowly-organised and rapidly-developing 
alga will mantle your water plants with their green 
slime, and strangle and suffocate them in folds of 
sickly-looking greenery. At the slightest sign of 
anything of this kind occurring, the aquarium ought 
to be put away from the light. A few days in a 
darker corner will soon restore it to its healthy con¬ 
ditions, if only the disease has been taken in time. 
Another means of keeping down the excessive growth 
of aquatic vegetation is by introducing more marsh 
snails, such as Paludina , the larger species of Pla- 
norbis ( P . corneus ), &c. These crawl over the inner 
surfaces of the glass and clean it, removing and de¬ 
vouring the green film ; they also keep down the 
tendency to too rapid growth in Anacharis , Callitriche , 
&c., on account of their fondness for the young and 
growing shoots. 


3 2 


PRINCIPLES OF THE AQUARIUM. 


Another evil threatening ah aquaria results from 
not attending to the temperature of the water. You 
see tanks placed full in the sunlight of the window, 
where the inhabitants are most exposed to the 
light and heat. We have noticed how the light 
thus received encourages the undue growth of vege¬ 
tation ; now we have only to remark on the sickly 
condition of the water when it is so thoroughly and 
directly heated by the sun. The temperature is raised 
far beyond what it could be in a pond or a stream. 
In the former the sides and bottom are always dark 
and cool, and in the latter the greater ease with which 
the sun can heat the shallow water is compensated 
by the constant change of the water in running. In 
an aquarium placed in the full sunshine it is evident 
that the animals and plants alike are exposed to most 
unnatural conditions. With the elevation of the tem¬ 
perature there is attended a less capacity for the 
water to contain the mechanically-mixed oxygen 
given off by the plants, or even to absorb it from con¬ 
tact with the air at the surface. Animal matter de¬ 
composes more readily, and thus the water becomes 
sooner fetid. What the student ought especially to 
observe, therefore, is that his fresh-water aquarium is 
placed where the temperature of the water varies as 
little as possible. It ought never to fall below 40° 
or rise higher than about 6o°, if he desires to keep a 
healthy stock of animals and plants. 

A well-constructed aquarium ought to continue 


CLEANSING AQUARIA, 


33 


in the same state for years. It is a common error 
among those who have had no experience in these 
matters (and very likely the notion has fostered the 
idea as to the great trouble which aquaria give) 
that the water ought often to be changed . Nothing of 
the kind. A well-balanced aquarium, one that has 
eventually “ got into good working order,” wants no 
water added to it except what may be lost by evapora¬ 
tion. If proper care be taken, even this may be reduced 
to a minimum. The best plan is to have the top 
covered with a plate of glass. It may be loosely 
placed there, and ought never to be fastened down, 
else there would be no means of getting at the con¬ 
tents of the aquarium. Such a plate of glass lessens 
the evaporation, and protects the surface of the water 
from dust. If we desire that the aquarium should be 
further ornamental, this may easily be done (with 
one of sufficient capacity), by having a fountain playing 
in the middle. Fewer aquatic plants are then required 
to aerate the water, as the fountain does it mechani¬ 
cally, entangling films of air on the surface of every 
drop of water thrown up. The plants may then 
be ornamental, such as the water violets (. Hottonia 
palustris ), water plantains ( Alisma plantago), &c. All 
that is required is a wide-mouthed bottle, in the cork 
of which are three holes though which the glass tubes 
seen in the sketch pass. C reaches nearly to the 
bottom, whilst the other two pass only through the 
cork. A is a wide, funnel-topped tube. C is bent at 

D 


34 


PRINCIPLES OF THE AQUARIUM . 


the top, and has there attached to it a piece of long 
indiarubber tubing. The cork and tubes should fit 
perfectly. In order to set this easily improvised 


Extemporised Fountain for small Fresh-water or Marine Aquaria. 

fountain in action you fill the bottle. When it is full, 
continue pouring water gently into the funnel until 
it is above the level of the bend in the tube C. A 
little will then flow over into the long leg of the 
















































FOUNTAIN FOR AQUARIA. 


35 


syphon E. The water will of course continue to 
flow until the level of the water in the bottle falls 
below the mouth of C. The tube B is for the escape 
of air whilst filling. A very short experience will 
enable the student to work this cheap fountain, and it 
is evident it will flow for a greater or less space of 
time according to the magnitude of the feeding bottle 
and the bore of the indiarubber pipe, which is bent 
upwards at its extremity for the purpose of throwing 
the water into the air. It is true, more water is 
wasted by evaporation in this manner, but this is a 
difficulty easily met, as sufficient fresh water can 
always be put in the service or feeding bottle. The 
fresh-water aquarium may be made prettier and more 
ornamental than it hitherto has been, with aquatic 
flowering plants, if only pains be taken to render 
their conditions of growth natural. There is no 
reason why we should not have aquatic gardens of 
this kind in our rooms. 

The dust which accumulates when the presence of 
such plants renders a closely-fitting glass plate impos¬ 
sible, can easily be removed now and then by gently 
laying pieces of blotting paper on the surface of the 
water. The dust adheres to it, and it is then easily 
removed. Or it can be skimmed off by using the edge 
of a sheet of writing paper. By a little skill and 
care, we might easily possess semi-aquatic gardens in 
which miniature fountains are made to play ; and the 
whole rendered a fit and healthy habitat for such 
creatures as can best be supported. 


D 2 


36 


FRESH-WATER AQUARIA 


CHAPTER IV. 

CONSTRUCTION OF FRESH-WATER AQUARIA. 

The construction of a moderate sized, portable fresh¬ 
water aquarium may be as cheap or as expensive a 
matter as a person thinks fit, or his pocket can afford. 
They can usually be purchased at the natural history 
dealers’ shops in London and elsewhere ; but perhaps 
one learns more of the conditions under which the 
animals we propose to keep will hereafter live, if we 
have the aquaria constructed under our own super¬ 
intendence. Having fully taken into consideration 
the principles which ought to guide us in maintaining 
aquatic animals and plants, the next thing is to be 
sure the aquarium will not leak ; and that it contains 
nothing in the materials composing it which are at all 
likely to be poisonous. Under the direction of a car¬ 
penter or plumber, any of the aquaria of which we give 
illustrations may be constructed. One of the cheapest, 
perhaps, is that shown in Fig. 2, and, by a little alter¬ 
ation in the internal details of rockwork, &c., it may 
be used for marine or fresh-water objects as the owner 
thinks fit. The back and sides are composed of strong, 
half-inch wood, dovetailed together. The bottom is 
thicker, and is screwed to the framework. The front 


CHEAP AQUARIUM. 


37 


only is occupied with plate glass, which is let in by a 
kind of “ rabbit and bead,” as carpenters call it. The 
whole of the interior of the woodwork, back, bottom, 

Fig. 2. 



Cheap Portable Fresh-water or Marine Tank. 


and sides, is then coated with pitch to the thickness 
of about one-eighth of an inch. Hot pitch is also run 
into the “ rabbit,” and the plate-glass front pressed 
well against and into it. If a wide beading is then run 
all round the top, the aquarium will be completed. 
Thus constructed, the whole expense will not exceed 
14s. or 15^. Before stocking it with animals and 
plants, the tank should be seasoned in rain water for 
a week or two; and can then be used without any fear 
of leakage or harm. A costlier method of constructing 
a tank on the same pattern is to have the bottom, 
back, and sides of slate, instead of wood, with a plate- 
glass front as before. 

There can be no doubt that aquaria with flat 
sides are much better than round bell-shaped glasses. 
They do not distort the objects when moving about. 













38 FRESH-WATER AQUARIA. 

after the fashion in which goldfish often present 
themselves to our notice in the ordinary globes. For 
a few pond snails and a plant of Myriophyllum, &c., 
as “ stock,” an inverted bell-glass with a wooden base, 

such as is shown in Fig. 3, may 
be used. It should be remem¬ 
bered, however, that only a very 
few objects can be thus accom¬ 
modated ; but if the owner have 
self-denial enough to forego the 
temptation of over-stocking the 
glass, such an aquarium may be 
healthily kept, and will even form 
a very pretty and lively little 

“ ” filacc 

ornament to a room. Again, a 
darkened bell-glass may be used as part of a more ela¬ 
borate attempt (Fig. 4), in which, by means of an ordi¬ 
nary cheap wire stand, it may occupy the centre and 
be surrounded with the ordinary flowering plants with 
which we are in the habit of decorating our rooms. 
A glass sheet protects the surface of the water in the 
aquarium from dust. The late Dr. Lankester, who 
was one of the best and earliest writers upon aquaria, 
showed in his ‘ Aquavivarium ’ that such an arrange¬ 
ment as this might be very easily and cheaply car¬ 
ried out. 

Another inexpensive tank, which answers well for 
window purposes, providing the sides and back are 
made of opaque material and not of glass, is shown 
in Fig. 5. The top may be fashioned of wood or zinc 














































BELL-GLASS AQUARIA 


39 


slightly perforated, and should have a narrow plate of 
glass let into the top. If the front only be made of 


Fig. 4- 



Flower-stand, with Bell-glass Aquaria. 


glass, the light will not prove too strong. We have 
used this kind of tank both for fresh-water and marine 









































40 


FRESH-WATER AQUARIA. 


objects. It should not be placed in a window having 
a south front, as the light then is too strong, and will 
develop that pest of aquaria, a thick opaque green- 


Fig. 5* 



Oblong Tank for Window Aquarium. 


ness, do what we may. A northern aspect is always 
the best for the glass frontages of aquaria to face, 
whether they be placed in windows or in rooms. 

In the construction of square or polygonal aquaria 
it is of course necessary above all things that the sides 
should be perfectly water-tight. Leakage is a source 
of annoyance and untidiness in a room, besides in¬ 
terfering with that balance of animal and vegetable 
life which is sought to be sustained in the water. The 
following will be found a good receipt for making a 
cement that will keep the sides and joints of a tank 
perfectly water-tight: fine white sand, one part; 
litharge, one part; resin, one-third part, mixed into a 
















































ROCKWORK FOR AQUARIA. 


41 


paste with boiled linseed oil, and applied unstintingly . 
A little rockwork is always an additional element of 
attraction in an aquarium, especially if fish or amphi¬ 
bia are kept. In fresh-water aquaria, however, it is 
never required to the extent it is in marine. When 
built up loosely, the darker places afford a screen 
from a too intense light, and those creatures which 
cannot bear it will soon discover such retreats. But 
this adaptation applies more to marine animals than 
the fresh-water forms of which we are especially 
treating. Newts love to crawl upon a stone or piece 
of rockwork projecting above the water, in order to 
bask in the sun; but this they will do if the water 
plants are strong enough to bear them on the surface 
of the water. The best and most harmless material 
for rockwork is pieces of pumice-stone, fragments of 
melted glass bottles, and such fragments of vitrified 
bricks as may be picked up in any brick-kiln. These 
should be fastened together with Portland cement. 
In order to make the contents of the tank as light as 
possible, one or two inverted flower-pots may be 
fastened to the bottom. If the inverted edges be so 
broken as to form a passage through, then the interior 
will serve as a dark cave to any of the animals re¬ 
quiring such a retreat. The holes (now uppermost) 
should not be filled up, for the water within the 
inverted pot will be kept colder, and thus a healthy 
current action between it and the surface water may 
be set in action through the holes. Flower-pots thus 


42 


FRESH- IVA TER A Q UARIA. 


serve a double purpose. They render the rockwork 
built around and over their external surfaces (except 
where the edges are broken at the bottom to form a 
tunnel, and the usual opening in the middle of the 
inverted base) lighter than it would be if it were 
heaped up, one solid piece on another. And we 
have already seen that the colder bottom and 
warmer surface waters will set up a feeble vertical 
current action. 

If aquatic plants are intended to form a part of the 
stock contents of the tank, the best plan is to procure 
them when young from some dyke or pond, and plant 
them in flower-pots. These flower-pots may be hidden 
among the rockwork ; nay, the latter may be loosely 
fastened around them by means of Portland cement so 
as to completely conceal them. Such species as the 
water violet, water plantain, water soldier, and arrow¬ 
head grow best when thus treated ; and as their flower¬ 
ing spikes ascend above the water whilst their leaves 
are mostly either submerged or floating, they form very 
pretty accessories to the larger fresh-water aquaria.* 
In the arrow-head, water ranunculus, and several 
others, the floating or surface leaves are of a different 
size and shape to the submerged leaves. All the plants 
just mentioned require a good depth of soil to be 
planted in, and their transference to flower-pots prevents 

* Such aquatic plants ought not to be kept where gas is lighted at 
night, as they are then unduly forced, and pine away from not obtaining 
their necessary repose. 


DUCKWEEDS . 


43 


the necessity of filling the bottom of the tank with 
the depth of soil or mud in which they require to grow ; 
and as these vertically-growing plants might be placed 
around the sides or at the ends of the tanks, more 
room would then be left for the evolutions of fishes or 
other aquatic animals. Hence, rockwork in the centre 
of fresh-water aquaria is to be shunned, as it both inter¬ 
feres with the movements of the objects and prevents 
us witnessing them. The surface of the water should, 
if possible, be partly covered with vegetation, for it 
keeps the water cool and forms a retreat for the smaller 
inhabitants, and also to some degree prevents undue 
evaporation. One or two of the many species of 
duckweed ( Lenina ) are useful in this respect, for none 


Fig. 6. Fig. 7. 



Ivy-leaved Duckweed (Lemna trisulca). 
Lesser leaved Duckweed (Lemna minor). 


of them need any soil. They derive what nutriment 
they require from the water in which they float, suck¬ 
ing it by means of the slender rootlets which may be 
seen let down from the layer of green frond-like 




44 


FRESH-WATER AQUARIA . 


leaves. These roots terminate in a spongy base, 
through which the work of absorption is carried on. 

In forming aquaria wherein it is intended to grow 
aquatic plants, a good deal of attention ought to be 
paid to the fact whether such plants require much or 
little soil. With the exception of the duckweeds, all 
require some, if only to anchor their roots in. But 
this mud should be dispensed with as much as pos¬ 
sible, on account of the tendency there is to thicken 
the water whenever fishes or other animals stir it 
up. The great water beetle ( Dyticus ) very often does 
this, especially in the night time ; and so you awaken 
some morning to find the water, which was clear the 
night before, in what seems a hopelessly muddy condi¬ 
tion ! Little if any soil is required by the Anacharis 
(a Canadian plant), one of the most useful an aqua¬ 
rium keeper can have if kept in proper bounds, for it 
grows only by shooting or budding, never by seeding, 
and many aquatic animals, fishes especially, are very 
fond of nibbling at the young green shoots. Another 
plant, equally useful and even more beautiful, is the 
star-wort ( Callitriche ), which requires a little sediment 
for its roots to be planted in. The leaves of the 
star-wort are much used by fishes and amphibia for 
depositing their spawn upon. The water crowfoot 
(Ranunculus aquatilis) requires little soil for its roots, 
but its needle-shaped leaves soon branch through and 
fill up the interior of the tank if too strong and old a 
plant be introduced. It is worth trying a little of this 


SOIL FOR AQUARIA. 


45 


common plant, however, if only for the sake of the 
pretty kidney-shaped floating leaves and its brilliantly 
white and abundant flowers. 

The best soil that can be selected for the purpose of 
covering the bottoms of fresh-water tanks is fine river 
sand, in which may be mixed a few small round stones. 
All should be well washed, or they may be the means 
of introducing into your aquarium objects you never 
bargained for, which will upset the equilibrium you 
so much desire to commence and maintain. A few 
pieces of charcoal mixed with it, are serviceable in ab¬ 
sorbing all decaying organic substances. These, how¬ 
ever, should be removed from time to time, when it is 
supposed they have taken up as much organic matter 
as they can. Charcoal also prevents foul smells, and 
generally acts as a deodoriser. Too much of it, how¬ 
ever, is likely to be injurious. In fitting up an aqua¬ 
rium the soil should be placed after the rockwork 
has been constructed and the water plants rooted 
in their concealed flower-pots. To prevent the soil 
being washed up and the water rendered muddy, the 
water must be poured in through the finely perforated 
rose of an ordinary watering can. The fresh water 
commonly used for drinking purposes will do, and this 
is perhaps better than if obtained from a pond, where 
there is likely to be much more diffused vegetable 
matter. The water weeds, both potted and planted, 
ought also to be well washed before they are trans¬ 
ferred, otherwise fish, amphibian, or molluscan spawn 


4 6 


FRESH- WA TER A Q UARIA. 


may be adhering to their stems and leaves, so that 
they are afterwards hatched. 

Let us suppose that all these directions have been 
attended to, the plants are growing in the recently 
poured in water, and the latter is clear and transparent. 
Now let it remain in this state for a day or two, when 
the plants will have recovered from the shock occa¬ 
sioned by their transference, and the water will have 
been tolerably well charged with the oxygen they 
have given off. Then add one or two animals, a couple 
?f minnows or newts, and a water snail or two, and 
watch the results. From what we have already said 
in the last chapter you will at once perceive whether 
there is a redundancy of animal or vegetable life, and 
be able to modify their relationship accordingly. 
When there is evidently a balance, endeavour to keep 
it. All the objects, animal and vegetable, which you 
have stocked the tank with, are mortal, and will 
sicken and die. You must at once remove dead bodies, 
or they will taint the water. A pair of wooden forceps 
will be handy for picking them up from the bottom 
where they are sure to be found occasionally lying. 
A little hand-net will also be found useful both for 
removing specimens and procuring them for further 
and minuter investigation. 

If fish are kept they require a little food, but the 
quantity is so small that it does not do to provide it 
for them artificially. On no account get into the habit 
of feeding fish or newts with pieces of raw beef, or even 


FOOD FOR FISHES. 


47 


earth worms. Whether they will accept them or not 
depends upon their capricious humour, and if they are 
not eaten they only accumulate on the bottom and foul 
the water. A much better plan is to keep as many 
snails as you possibly can. Their spawn is a favourite 
food with fish, and what with that, animalculae, ento- 
mostraca, and the fresh shoots of aquatic plants, they 
manage to make all the feeding they require. If fresh¬ 
water animals have to be artificially fed the best diet 
is the blood-worm ( Tubifexrivulorum ), which is to be 
found in many ponds and streams. Many fish eat it 
greedily, and it has the advantage of being an aquatic 
worm, so that if it be not eaten at the time you put it 
in the tank, it lives to be eaten another day! The 
fine blood-red colour of this worm is due to the false¬ 
hood being visible through the thin skin. 

We have seen that the gradual change of the water 
to a greenish hue is due to the presence of minute 
vegetation which the undue light has stimulated into 
existence, and that the remedy for this was to sub¬ 
due the light until the evil was overcome. Now we 
have to notice another unhealthy condition of things 
to which the inhabitants of a fresh-water tank are 
liable. Occasionally the weeds are covered with a 
white hairy slime, and the water gets thick with a 
muddiness which is evidently due to the same cause 
as the condition of the plants. Perhaps you will also 
notice the fishes gasping on the surface, as if they 
were unwilling to breathe the foul air mixed with the 


4 S 


FRESH-WATER AQUARIA. 


contaminated water. These symptoms are due to 
want of air ; and when you perceive them, at once 
remove the aquarium to where it will receive an extra 
stimulancy from sunshine and oxygen. If this does 

not immediately remedy the evil, 
remove one or two of the fish or 
newts, or other of the larger animals 
to a temporary glass, such as is 
shown in Fig. 8, where there are 
plants of Vallisneria , &c., growing. 
This is one of the best oxygen¬ 
giving, fresh-water plants we have, 
and may be used in small tempo¬ 
rary jars or glasses for the purpose 
of so aerating the water that it 

containing acts as a restorative, and the glass 

Vallisneria is the best re- thus serves as a kind of conva- 
stormg plant. 

lescent hospital. If a large aqua« 
rium is kept, or more than one, an infirmary of this 
kind will be found very useful.* 

We repeat it, that the only successful way in which 
aquatic animals and plants can be maintained in a 
healthy condition, is by endeavouring as far as possible 
to imitate natural conditions. This, however, presumes 

* It will be noted that all the foregoing directions apply only to 
streamless fresh-water aquaria. When opportunity affords (as it often 
may do) of constructing them so that the water may be conducted by a 
pipe from the usual household supply, and a constant circulation and 
aeration can be kept up, much labour will be saved, and the objects 
will appear more healthy and active. 


Fig. 8. 



i i ^ « 4 - ^ 





























VA LLISNERIA . 


>9 

a more intimate knowledge of natural history than 
most people possess, and in such cases, therefore, all 
we have to do is to attend to the above general in¬ 
structions, until such time as experience will have 
been able to suggest some other course. Every set 
of animals and plants has different habits to another, 
and we should never fall into the error of supposing 
that because we have been successful with one group, 
exactly the same treatment cannot fail to be effective 
with another. To the aquarium keeper as well as 
to the profound naturalist, the motto of Longfellow 
equally applies— 

“ Learn to labour and to wailV 


E 


AMPHIBIANS AND FISHES. 




CHAPTER V. 

AMPHIBIANS AND FISHES OF THE FRESH-WATER 

AQUARIUM. 

It needs little scientific knowledge to perceive that 
an aquarium keeper is likely to be far more successful 
if he attempt to keep a few animals, than if he over¬ 
crowd his tank with many. It cannot be too strongly 
insisted upon, that more than half the misfortunes and 
so-called “ bad luck” which are ordinarily experienced 
in the keeping of aquaria, are due to overstocking ; 
When a few objects only are kept it is surprising how 
healthy and vigorous they appear. Moreover, they 
sooner get tame, or rather accustomed to their keeper, 
than when they are numerous. It is always best to 
keep more than one individual of the same species if 
the tank be large enough, otherwise there is a sense of 
loneliness suggested which detracts from the pleasure 
of preserving animals ; and before long one sees that 
the solitary pets feel this themselves. Two small 
fishes or newts are always preferable to one. 

Nearly all our native species of animals can be thus 
kept in captivity. Recently such amphibians as the 
pretty yellow-spotted salamanders, and those still more 
curious creatures the Mexican axolotls have been in- 


SALAMANDERS. 


51 


troduced, and aquarium keepers can now purchase 
them alive at any of the London naturalists. Still, we 
doubt whether either of these exhibit so much intelli¬ 
gence as our own newts, or if they exceed them in 
beauty. The great water newt (Triton cristatus), Fig. 9, 



Fig. 9. 


Great or common male of Water Newt (Triton cristatus ). 


notwithstanding the roughness of its warty skin, has 
a bright orange colour on the under part of the body 
which gives it a very attractive appearance. Its move¬ 
ments in the water are even more graceful than those 
of fishes. These animals have long been regarded with 
dislike and suspicion, and not many years ago farmers 
believed they could cause rheumatism and paralysis 
to cattle by creeping over their limbs. Even yet this 
superstition may be found lingering in out-of-the-way 
corners of England. We have ourselves heard myste¬ 
rious diseases and complaints in cattle attributed to 
their drinking pond water in which newts were known 
to be abundant! The readiness with which country 
lads pelt newts to death even yet, is a “ survival ” of 
this ancient and ignorant prejudice. We need not 
say how thoroughly without foundation is this notion, 
or descant on the cruelty to which it has given rise. 


E 2 








52 


AMPHIBIANS AND FISHES. 


The presence of a serrated crest along the back is 
characteristic of the males both of this species and 
that of the smooth newt. The latter, however, may 
easily be identified by its smooth skin and smaller 
size. 

Both male and female of the great warty newt are 
easily tamed. We have kept them until they would 
come to the top of the water and take a worm from 
our fingers. They are voracious feeders, but it is best 
not to supply them with too much food. When they 
are in season, the tadpoles of the common frog will be 
found the best diet to give them. These do not taint 
the water as worms are apt to do when they die; 
and it is very interesting to witness the schemes and 
pursuits the newts indulge in to capture their second 
cousins. It will be as well not to keep this species 
and the smooth newt (Lissotriton punctatus) in the 
same tank, otherwise the latter may fall a victim to 
the ready appetite of the former. Even if it does not 
it is placed in hourly dread, and shelters itself so that 
it can rarely be seen. All the newts use their verti¬ 
cally flattened tails for swimming. The weakness of 
their legs on land adds to their reptilian appearance, 
for they are obliged to crawl, and are by no means so 
agile as the lizards for which they are frequently mis¬ 
taken. On hot summer days you will see the newts, 
with their legs extended, floating and basking on the 
surface of the water. 

It is only in the spring and summer months that 


NEWTS. 


53 


the males of these two species of newts have the 
dorsal crest fully developed. Like many other 

animals, birds especially, the sexes are reduced to 
a common likeness during the winter. When the 
warmth of later spring begins to be felt, it is 
astonishing how quickly the dorsal crest, and the 
characteristic colours and the spots of the males, 
are developed. In May and June these will be at 
their height, for the females are then depositing their 
ova, singly, in the folds of the leaves of the water 
plants. The eggs are soon hatched, and, as is well- 
known, the tadpoles are en¬ 
dowed with external gin- 
tufts (Fig. io). 

The great warty newt is 
the best for the fresh-water Tadpole of Newt (three months 
aquarium, on account of its 

greater fondness for the water. It rarely leaves 
it, except to bask on the leaves, or on some stone. 
Hence it is as well to have a little rockwork projecting 
above the surface of the water in which these newts 
may be kept. During winter, it will lie torpidly at 
the bottom of the tank; but if the latter be always 
kept in doors (as it ought to be), the period of 
hybernation will be very brief. Perhaps the reason 
why the crest is lost in winter is that it becomes 
absorbed, in lieu of food, by the system, to maintain 
the action of the involuntary organs. There is a 
popular error that the tadpoles of frogs and toads 



54 


AMPHIBIANS AND FISHES. 


drop their tails and gills when they leave the water 
for the land. The real fact is that both these organs 
are absorbed and utilised, and are not dropped or 
shed at all. 

The smooth newt is quite as common as the warty, 
and its habits are perhaps quite as interesting to the 
observer. The dorsal crest of the male is not toothed, 


Fig. ii. 



Adult male of Smooth Newt. 


Fig. 12. 



Adult female of Smooth Newt. 


like that of the warty newt, although it is wavy in its 
outline. Both male and female indulge in graceful 
evolutions, and not unfrequently may be seen chasing 
each other in frolicsome sport. The female is exceed¬ 
ingly cautious in selecting the proper places for the 
deposition of her eggs ; and the process of laying them 
singly or in pairs, and afterwards of folding up the 
leaves of the plant around them, so as to screen them 













































TADPOLES. 


55 


F'g- 13- 


from the keen eyes of other aquatic animals on the 
look-out for food, is very interesting. If the plant be 
present, the female smooth newt always seems to 
prefer the leaves of the 
Callitriche for this purpose. 

This plant is very common, 
and is one of the best that 
can be selected for fresh¬ 
water aquaria. The crea¬ 
ture maybe seen examining 
one leaf after another until 
she has selected one that 
appears to answer her pur¬ 
pose better than the rest. 

The eggs are laid at an 
interval of three or four 
weeks. Under the micro¬ 
scope these eggs become 
very interesting objects, in¬ 
asmuch as the transparent 
membrane allows every 
stage of the development 
to be plainly seen. 

The claspers are used by Callitriche, showing leaves folded 
f , , 1 ,, <-' v er eggs of Smooth Newt, 

the young tadpole to hold 

on to any object there is in the water, for it is only 
after a brief experience that it is able to regulate and 
control all its own movements. 

Water fleas ( Daphnia ) and the blood-worms already 




56 


AMPHIBIANS AND FISHES. 


mentioned, are the best food for the smooth newts. 
If these are supplied in abundance the newts will 
rarely leave the tank. Indeed, there is much reason 

Fig. 14. Fig. 15. 



Tadpole in egg eight days after laying. 
The arrows indicate the current motion 
caused by the cilia. The dotted lines show 
the increased growth eleven days after the 
egg was laid. 



Development of tadpole in egg 
seventeen days after the laying of the 

egg- 


Fig. 16. 



Earliest stage of the free tadpole of smooth newt— a , claspers j fore¬ 
leg partly developed; c, circulation of the blood ; d , transparent fin ; 
e> branchiate, or gill-tufts. 

to suppose that one cause of their leaving is the ab¬ 
sence or shortness of food supplies. They are very 
curious animals, and will come to the inner surface of 
the glass of the tank to examine anything unusual, 
















DEVELOPMENT OF NEWTS. 


57 


or even when you are observing the movements of 
any of the creatures through your magnifying glass. 
One of their habits is that of casting their skin, which 
is sloughed off whole, so that it can be afterwards 
collected and mounted. This process usually takes 
place when the breeding season is over, and male and 
female are assuming their winter skins. 

We have one or two other native species of newt 
which are much rarer, and more locally distributed 
than the above, which would do equally well as objects 
for the aquarium. These are the straight-lipped warty 
newt (Triton Bibronii), and the palmated smooth newt 
(Lissotriton palmipes ), found near Tooting. The de¬ 
velopment of the spawn of frogs and toads might also 
be usefully studied in an aquarium, although care 
would have to be taken that the quantity introduced 
was not too great for the aquatic vegetation to supply 
with oxygen. Very little attention has hitherto been 
paid to the development of these common objects, 
but there is no reason to believe it would be less 
interesting than that of the newts. Although resem¬ 
bling each other so much, the spawn of frogs and 
toads may easily be identified by the fact that the 
former occurs in lumps and the latter in single strings. 
The eggs of toads are about a quarter of an inch in 
diameter, and usually smaller than those of frogs. 

Where there is an abundance of newt or frog spawn 
developing, several small fishes might be preserved to 
keep down its undue development, always providing 


AMPHIBIANS AND FISHES. 


5 * 

that the capacity of the tank is sufficient to allow of 
necessary vegetable growth to provide them with air. 

Of all the favourite species the goldfish has long 
been most domesticated, so that now, like the canary 
among birds, it seems to be better adapted to confine¬ 
ment than even to a free roving life. It will answer 
admirably in a tank supplied with Anacharis , the 
tender shoots of which it eats with great relish. This 
and an occasional blood-worm will serve for all the 
food it requires. Where fish are kept the utmost care 
should always be taken that no bread or biscuits are 
ever given to them, as these not only injure the fish, 
but contaminate the water by their speedy decompo¬ 
sition, unless the water is exceedingly well oxygen¬ 
ated. Care has also to be bestowed upon the Ana¬ 
charis in such tanks as may contain it, for, as its only 
method of reproduction in this country is by budding, 
the latter process is apt to take place so vigorously as 
speedily to fill the water with a densely-crowded mass. 
It may always be made to grow by planting a sprig 
in a flower-pot containing soil, and placing this among 
the rockwork, so as to be hidden away. 

Undoubtedly those of our native fishes which are 
easiest to obtain and domesticate are the stickle¬ 
backs and the minnows. We have several species of 
the former, some of which will live equally well in 
fresh and salt water aquaria ; and as some of them 
indulge in the unfishlike recreation of nest-bnilding ; 
they become really very interesting objects when the 


STICKLEBACKS. 


59 


tank is clear enough to enable one to witness their 
habits of life. They are, moreover, pugnacious little 
fellows, and will attack other aquatic animals, or get 
up fights among themselves, as if they had been 
geographically limited to the “Emerald Isle.” You 


Fig. 17. 



Three-spined Stickleback engaged in nest-building. 


may witness the male fishes carrying bits of weed, &c., 
in their mouths, and building up a heap in some corner 
in this manner. This work finished, their next task 
is to induce some of their female companions to come 
there and deposit their eggs. Whilst engaged in this 
courtly office the males assume the most lovely pris¬ 
matic hues, especially about the head and shoulders. 
The females deposit their eggs or spawn, and then 
leave it to their male companions to defend the spot 







6o 


AMPHIBIANS AND FISHES. 


against all spawn-loving fish, until such time as it is 
hatched. Even then the labour is not over, for we 
may see the paternal fish hovering about the young 
fry with the greatest anxiety, and valiantly running 
tilt against all other animals, those of their own spe¬ 
cies included, who may be desirous of making further 
acquaintance with them. The commonest of these 
little fish is the rough-tailed or three-spined stickle¬ 
back (Gasterosteus trachurus ). The male will attack 

Fig. 18. 



Rough-tailed Stickleback (Gasterosteus trachurus). 

anything that comes near his nest, even the carnivorous 
water tigers and water beetles. Another species is 
Gasterosteus semi-armatus, very common in some 
streams and rivers, and this also constructs a nest, 
and generally adopts the habits above described. 

Nearly allied to the sticklebacks in many respects 
is the Miller’s thumb, or river bull-head ( Cottus 
gobio). In many rivers they are very abundant, so 
there is no difficulty in procuring them. In the 
aquarium they are active and wary little animals, 
loving to hide under the loose stones. 

The loach ( Cobitis barbatula ) is another interesting 
little fish that may be readily domesticated. As its 



GUDGEON, ETC. 


6 1 


barbules would lead anyone to infer, it is a bottom 
feeder, and its colour and markings are such as readily 
to hide it from observation when in its natural habitat. 

Fig. 19. 



The Loach (Colitis barbatula). 


Like the miller’s thumb, it often hides under the 
stones, or in the interstices of rockwork, but it is by 
no means so voracious. I11 the aquarium it, as well 
as most fishes, is very useful in devouring any odd 
worm or dead insect or fragment that may have been 
lying on the bottom of the tank, and that otherwise 
would have decomposed and contaminated the water. 

The gudgeon (Gobio fluviatilis) is even a greater 
favourite with some aquarium keepers than stickle- 


Fig. 20. 



The Gudgeon (Gobio fluviatilis ). 


backs. It grows to a larger size, often to 6 inches in 
length, and is therefore a more attractive object. It 
may readily be identified by the pair of barbules, or 





62 


AMPHIBIANS AND FISHES. 


feelers, one on each side the mouth. If this fish is 
kept, the bottom of the tank should be covered with 
sand and gravel, not mud, or otherwise the water will 
be fouled by its habit of stirring up the bottom. It 
is a voracious feeder, and will eat up any animal 
garbage that may be lying about. It is best to keep 
several of these fishes in the same tank, as they are 
very social in their habits, and will not live long 
solitary. 

The minnow ( Cyprinus, or Phoxinus l<zvis) is 
another of our commonest little fresh-water fishes, 


Fig. 21. 



Minnow (Phoxinus Icevis). 


and remarkable for assuming prismatic colours during 
the spawning season, after the manner of the male 
sticklebacks. Like the gudgeon, it is gregarious, and 
usually found in shoals ; but, unlike it, it is fonder of 
the surface, where it can bask in the sunshine, than 
of the bottom of the water. It lives as well in con¬ 
finement as the sticklebacks do, and is quite as 
vivacious and attractive. Indeed, many people prefer 
it to the stickleback, on account of its more peaceful 
habits. 

The pope {Perea fluviatilis minor) is a beautiful 
fish, a well-marked variety of the common perch. 






MINNOW AND PERCH . 


63 


Although not so easy to preserve in the aquarium as 
the foregoing, a little extra attention will be sufficient 
to keep it in good health for a long period of time. 

Fig. 22. 



Common Perch {Perea fiuviatilis). 


It grows from 4 inches to 6 inches in length, and 
forms a very conspicuous object, moving to and fro 
over the bottom of the tank in search of caddis- 
worms, blood-worms, Crustacea, &c. It loves to swim 
boldly about with its dorsal fin erected, and then 
looks as if engaged upon some crusade. 














































































64 


AMPHIBIANS AND FISHES. 


The common carp and Prussian carp (Cyprinus 
carpio and Cyprinus gibelio) are both fishes which 
may be easily kept in our larger fresh-water aquaria. 


Fig. 23. 



Common Carp (Cyprinus carpio ). 


The former grows to a great size, but might easily be 
removed when it is too big for its tank. Both these 
fishes live to a great age, and are very tenacious of 
life, the latter especially so. When of the length of 
three or four inches the common carp is a very useful 
and even an attractive fish. It is a good scavenger, and 



























CARP AND BLEAK. 


65 


feeds equally on vegetable and animal food. When 
young the bronze tinge gives them a very pleasing 
appearance. During the winter their habits are very 
sluggish, even when the aquarium is kept within 
doors; and then they eat next to nothing, but pass 
the time in a semi-hybernation. The Prussian carp 
is even prettier than the above- mentioned species, pos¬ 
sessing a brighter colour and a more graceful shape. 
It is very fond of warm water, and breeds in enormous 
numbers in the fresh-water “lodges” or reservoirs into 
which the steam-water flows from manufactories in 
the north of England. No more hardy or useful fish 
could be placed in the tank than this. The bleak 
(Cyprimes alburnus) is another interesting and useful 


Fig. 24. 



The Bleak (Cyprinus alburnus). 


fish, one that will give little trouble, and which, 
in the larger tanks, will prove of great serviee in 
clearing away decomposing organic matter of all 
sorts. Not long ago the scales of this fish were used 
and ground up for the manufacture of artificial pearls. 
The shape of these fishes is very graceful. They 


F 


66 


AMPHIBIANS AND FISHES. 


usually move in shoals, hence it is necessary to keep 
several of them together. 

The roach (Cyprinus rutilus , or Leuciscus rutilus) 
is an attractive object in the aquarium, although 


Fig. 25. 



The Roach (Cyprinus rutilus , or Leuciscus rutilus ) and Dace 

(L. vulgaris'). 


more difficult to keep than many of those we have 
mentioned. When young, and free from the black 
cancerous growth on the scales which disfigure so 
many of the older and larger fish, it is so active and 









































ROACH AND DACE . 


67 


healthy that we cannot wonder at the common saying, 
“As sound as a roach.” Its bright red fins assume 
their most gorgeous tints about breeding time. A 
nearly allied species, common in Norfolk, is the rudd, 
so called on account of its still brighter tints of red. 
When young this species may be domesticated, and 
kept healthily alive for some time, especially if the 
surface of the water be covered with aquatic vege¬ 
tation, for it is very fond of hiding under the cool 
shelter of such a layer, and darting out thence sud¬ 
denly and vigorously on its prey. 

In the larger tanks the perch may be kept with 
comparative ease, although it is a fish very capri¬ 
cious as to diet. It is always best to begin with 
small specimens, or those that are about a quarter 
grown. A perch of two or three ounces weight is 
quite big enough for ordinary size tanks, especially if 
other animals are kept with it. In the larger ones 


Fig. 26. 



The Pike (Esox lucius). 


small pike {Esox Indus') may be preserved, but Dr. 
Lankester calculated that a pike which weighs a 
pound will require a tank containing 32 gallons of 

F 2 



68 


AMPHIBIANS AND FISHES. 


water, besides a forest of aquatic plants to decarbonise 
and oxygenate it. This estimation is perhaps too high, 
but there can be no question of the large quantity of 
water required, especially in tanks where there is not a 
constant change by circulation. The pike may be fed 
with minnows or small roach, which will swim about 
until captured. This generally takes place in the 
early morning, for pike love to bask in the mid-day 
light, and are then so oblivious of external things that 
one of the modes of capturing them is by passing a 
running noose of copper wire over their heads whilst 
they are thus meditating. Much has been said re¬ 
specting the acclimatisation of the Silurus in this 
country, and the general establishment of aquaria 
might tend to settle the question of its practicability. 
This fish is tolerably common in Germany, Norway, 
and Sweden, where it grows to a large size. Many ich¬ 
thyologists have believed that it could be introduced 
with advantage into many of our rivers and lakes, 
where it might be cultivated as an additional staple 
of human food. Its flesh is said to be of excellent 
flavour when properly cooked. As the long barbules 
near the mouth indicate, it is a bottom feeder. It is 
stated to attain the weight of fifty-six pounds in 
four years, in waters where food is abundant. The 
longest of the barbules seem to be put to the same use 
as the dorsal spines are with its marine representa¬ 
tive the angler, or fishing frog (Lopkins piscatorius). 
Yarrell, who wrongly gives the silurus a place among 


THE PIKE. 


69 


British fishes, states that it is sluggish in its habits 
and a slow swimmer, and that it takes its prey by 
lying in wait for it like the fishing frog. From the 
extensive geographical distribution of this fish there 
can be little doubt it might be acclimatised in English 
waters. In 1865, fourteen live specimens were intro¬ 
duced to the Thames, and subsequently Mr. W. A. 
Lloyd introduced many more, but all appear to have 
died. 

Another fish, not uncommon in North American 
lakes and rivers, might be introduced into our larger 
fresh-water aquaria, and be the means of enlightening 
the general public as to the nature of by far the 
larger number of fishes which lived during the Primary 
epoch, and whose fossil remains occur so abundantly 
in the Devonian and carboniferous rocks. During 
those epochs this class of fishes reached its maximum, 
and ever since has been slowly dwindling away. Only 
a few species, forming about three per cent, of all the 
fish fauna of the world, remain to represent a once 
dominant and cosmopolitan race. We allude to the 
Ganoid fifties, so-called from their bony scales being 
covered externally with a glossy enamel. The stur¬ 
geon belongs to one division of this interesting group, 
and, notwithstanding its migratory habits, the latter 
seems to have done well in the Brighton and other 
aquaria. We are not aware whether the North 
American gar, or bony pike (Lepidosteus osseus ), has 
yet been introduced into England. It is a gracefully 


70 


AMPHIBIANS AND FISHES. 


shaped fish, and we have seen specimens nearly 
3 feet in length, whose whitish enamelled plates re¬ 
minded us strongly of what many of the ancient 
primary fishes must have been. The habits of this 
suggestive fresh-water fish very much resemble those 
of its English namesake, hence, no doubt, the reason 
why it was called “ gar-pike ” by the colonists. We 
hardly need point out the advantages which large 
aquaria possess in making us acquainted with the life- 
history of desirable fishes, before we attempt their 
acclimatisation for ulterior purposes. Hitherto we 
have done this quite at a venture. 


AERATING LARGE AQUARIA . 


71 


CHAPTER VI. 

THE AQUATIC GARDEN AND ITS PLANTS. 

UNTIL within a year or two ago the circulatory 
system of aerating large aquaria was confined to 
salt water. After Mr. Lloyd applied it thus, at 
Plamburg, in 1868, Mr. Saville-Kent applied it to 
the fresh-water tanks in the Manchester Aquarium 
with some success. The chief means of aerating the 
water was either by means of fountains, or through 
the agency of aquatic plants. Of course it will be 
impossible to amateur keepers of aquaria to aerate 
their small reservoirs by mechanically circulating the 
water. Such a process would be troublesome, and 
would hardly repay the large expense and outlay 
of labour by the small returns that would be afforded. 
Moreover, one reason for keeping aquaria in rooms 
is on account of their pretty and attractive appear¬ 
ance, and this would not be so effective without the 
greenery of aquatic or semi-aquatic vegetation which 
they usually possess. It is true Mr. Kent found that 
fishes suffering from the attacks of a white fungoid 
growth quickly recovered when placed in tanks 
aerated by circulation. Mr. Kent is of opinion that 
the fungoid growth is due to the lime in the water. 



7 2 


THE AQUATIC GARDEN. 


In this opinion we cannot agree. First, we are not 
aware that lime is at all an adjunct to the growth of 
microscopic fungi, and the Manchester water is 
singularly free from it as compared with that of most 
towns. We believe the fungoid growth to be due to 
a surplus of nitrogenous matter in solution, caused, 
perhaps, by the decay of animal substances to which 
tanks are liable if not properly attended to. Nitrogen 
is a necessity and stimulant to the growth of fungi of 
all kinds, and it is evident that the removal of affected 
fishes to clear running water where nitrogen is absent 
would counteract the disease. It has long been known 
to keepers of fresh-water aquaria that the best way to 
cure fish affected by the white fungus was to remove 
them to a tub where the water was constantly dripping 
from the tap. We have referred to this matter at 
length because it is one that cannot fail to interest 
aquarium owners. 

A judicious selection and grouping of aquatic vege¬ 
tation adds greatly to the beauty of a fresh-water 
quarium; and we have hinted how plants requiring 
deep soil, as well as those requiring little or none, may 
be accommodated in the same tank, by planting the 
former in ordinary flower-pots. These may be so 
arranged along one or other of the sides as to be 
only just covered with water, and then it will be pos¬ 
sible to grow such semi-aquatic plants as the lovely 
buck-bean (Menyantkes trifoliata ), sun-dew {Drosera 
rotundifolia and anglica) y Polygonum amphibium , the 


FUNGI ON FISH. 


7 3 


flowering rush (Bntomus umbellatus ), the water mint 
(Mentha aquatica), mare’s tail (Hippnris vulgaris) 

Fig. 27. 



Mare’s Tail (Hippnris vulgaris). 


and others. Our native vegetation offers consider¬ 
able choice, and for the beauty of the foliage and 

























































74 


THE AQUATIC GARDEN. 


flowers of some even of the commonest species, it 
would be difficult to find an equal number of foreign 
plants that would excel them in this respect. It 
should be remembered, however, that the main thing 
in the selection of aquatic plants is to have such 
species as will most effectively oxygenate the water. 
And it is always best to have the vegetable element 
slightly in excess of the animal, inasmuch as it can be 
more effectually managed, either by elimination, or 
by moderating the light which stimulates its growth. 
The common American weed (Anacharis alsinastum ) 
has never yet been known to flower or seed in this 
country. It is propagated solely by budding, and we 
have already said that fish, and especially goldfish 
and carp, are very fond of nibbling the young and 
tender shoots. A little of this plant may therefore 
always be advantageously introduced into a tank of 
moderate capacity. It must be seen, however, '.hat 
its tendency to rank growth does not interfere with 
other and more ornamental plants. 

Another species which has long been utilised in 
this country by druggists, to oxygenate the water in 
which medical leeches are kept, is the Vallisneria 
spiralis. It is a native of the south of Europe, but 
has been pretty extensively distributed in England. 
This plant is undoubtedly one of the best and most 
copious yielders of oxygen of all common fresh-water 
species, and therefore is of great service in small 
tanks. Its grass-like leaves show the circulation of 


VA LLISNERIA. 


75 


the protoplasmic granules under the microscope, like 
the blood corpuscles in the web of a frog’s foot. This 
plant roots freely in a little sandy earth or mnd. The 

Fig. 28. 



male and female flowers are borne separately, the 
latter having the long spiral stalks which have given 
to the plant its specific name. These float on the 
surface of the water; whilst the male flowers are 
borne on short stalks at the base of the plant. They 
are detached thence just before opening, and rise to 
the surface to fertilise the female flowers with their 
pollen. 
























76 


THE AQUATIC GARDEN . 


Few flowers exceed in beauty the yellow and white 
water lilies of our English streams and lakes (Nuphar 
lutea and Nympha alba). The space they take up, 
however, is so great that they can only be introduced 
into very large tanks, or into the basins of garden 
fountains. Their broad, cool leaves form an admirable 
retreat and screen for fishes, especially in the heat of 
a summer’s noonday. The perfume of the flowers of 
the former plant has obtained for them the name of 
“ brandy-bottles ” in some parts of England. The 
flowers only rise above the surface and open in the 
full blaze of day—at night the petals close and the 
flower head is withdrawn into the water. The water 
plantain (Alisma plantago) is a pretty aquatic plant, 
whose panicles of pale liliac flowers rise above the 
water very prominently. Its name is derived from 
the resemblance of its leaves to those of the common 
plantain. The flowers secrete honey from twelve 
glands they possess, for the purpose of attracting 
insects to bring about the cross-fertilisation which 
is so important an element in the propagation of 
many flowering plants. The arrow-head (Sagittaria 
sagittifolia ) belongs to the same order as the last- 
mentioned species, and is another true aquatic plant 
which may be included in our list of those intended 
mainly for ornamental purposes. Its common name 
is derived from the conventional arrow-head shape of 
the bright green leaves. The flowers are very pretty 
whilst they last, being white with pinkish spots at the 
base of the petals. The upper ones bear stamens 


WATER PLANTAIN. 


77 


only, and the lower pistils. In this order of plants 
also we should not forget to mention the flowering 

Fig. 29. 



Water Plantain (Alisma plantago). 

rush (Butomus umbellatus), one of the prettiest of all 
our native species. It requires to be planted in soil 


































THE A Q VATIC G A EDEN. 


78 

placed in a flower-pot, and hidden away in rockwork, 
as already described. The bright rose-coloured flowers 


Fig. 30. 



Arrow-head (Sagittaria sagittifolia). 

then rise from amid the three-cornered, sword-shaped 
leaves in large flat umbels. The root of this lovely 












































FLOWERING RUSH. 


79 


plant is believed in Russia to be a cure for hydro¬ 
phobia, but evidently without reason. 

Fig. 31 - 



Flowering Rush (Butomus umbellatus). 


Among other native or ornamental plants which 
may easily be adapted to the aquarium are the marsh 









































So 


THE AQUATIC GARDEN, 


forget-me-not, water mint, brook lime, water violet, 
polygonum, and buck-bean. The first (Myosotis palus - 
tris), also goes by the name of “ scorpion grass.” 

This is the veritable forget-me-not of the legend, and 
forms an exquisite adjunct to an aquarium, especially 
as a surface bordering. The flowers are coiled up in the 
crozier shape peculiar to the unopened fronds of ferns, 


Fig. 32. 



Water Mint (Mentha aquatica ). 


before they expand. The water mint (.Mentha aqua¬ 
tica) gives out a graceful perfume, especially in the 















































BROOK LIME. 


81 


evening, whilst its clusters of pale liliac flowers are 
unobtrusively pretty. The brook lime ( Veronica becca- 
bunga) is noticeable for its bright green leaves and 

Fig. 33- 



Brook Lime (Veronica becca-bunga). 


deep blue flowers. A nearly allied species is the 
water speedwell (Veronica anagallis) } whose flowers 
are paler, and rise above the water in loose panicles. 
The brook lime has to be looked after, otherwise it de¬ 
velops too rapid and rank a growth. The water violet 
(Hottonia palustris) is another of our prettiest English 
plants, as anyone will acknowledge who has seen the 

G 

































8 2 


THE AQUATIC GARDEN. 



ditches full of it in Norfolk and Suffolk. Its sub¬ 
merged leaves are feathery, like those of the water 


Water Violet [Holtonia fialustris). 

ranunculus, only larger and prettier; whilst its up¬ 
right hollow stem is surrounded with whorls of deli- 




























































































BUCK-BEAN. 


83 


cate five-petaled, liliac-coloured flowers. Polygonum 
amphibium is an aquatic species which may be easily 
transferred to a tank, and which readily flourishes 
there. Its bright, light-red flower spikes raise them¬ 
selves just above the semi-floating leaves, and look 
very pretty indeed. But of all our British plants 
affecting moist habitats, surely none is so lovely as 
the buck-bean (.Menyanthes trifoliata). It will not 


Fig. 35 



Buck-bean (Menyanthes trifoliata). 


flourish in the water, but may be so potted as to grow 
on the margin, at the top of rockwork which may be 
arranged at one end of the tank. In this position its 
bright deep green trifoliate leaves, and pale pink and 

G 2 









8 4 


THE AQUATIC GARDEN. 


white, feathery, lace-like flowers, cannot fail to obtain 
sincere admiration. In Lancashire this plant is much 
esteemed and gathered by the common people, the 
intense bitter of the leaves being esteemed a good 
stomachic. In Sweden and Norway the leaves are 
used in brewing beer, instead of hops. The plant has 
the floral peculiarity of bearing two sets of flowers, 
and is therefore dimorphous. 

We now turn to those common plants which are 
more distinctly aquatic than some of those we have 
just noticed. Of these by far the most widely dis¬ 
tributed is the water crowfoot (Ranunculus aquatilis). 
It bears two sets of leaves, those intended for floating 
on the surface, which are broad and slightly lobed ; 
and others which are always immersed. The latter 
are the most numerous, and are thread-like and 
feathery, often growing so fast as to form dense 
tangles. The flowers are pure white, with numerous 
yellow stamens. They rise singly above the water, and 
may be seen covering our ponds with a perfect carpet 
of flowers. The water ranunculus is a famous hiding 
place for aquatic objects. Water spiders build their 
queer, “ diving-bell ” like nests amid its leaves ; insect 
larvae hide in the depths of its thickets ; rotifers attach 
their frail cases to its tiny threads ; fishes of all kinds 
lie in wait or hide from enemies, or cool themselves 
beneath its dense and almost impenetrable foliage. 
No aquatic plant is more useful for the aquarium, or 
trained with greater ease; but, Rke the A nacharis, it has 


FROG-BIT. 


85 


to be prevented from usurping the entire tank. Even 
more beautiful than this is the frog-bit, whose kidney¬ 
shaped, bronze-coloured leaves are most exquisitely 



Water Frog-bit (Hydrocharis morsns-rance). 


meshed with veins. The plant is very tenacious of 
life, and may readily be accustomed to the aquarium. 
The flowers possess three petals, and are white and 
fragile looking. The water soldier (Stratiotes aloides) 
is a very abundant plant in Norfolk and Suffolk, as 
anglers thereabouts have long since discovered. It 
has to be planted in deepish soil at the bottom of the 
tank. Its leaves are thick and strong, and fringed 
with a margin of recurved spines like those of the 
aloe, whence its other name of the “water aloe.” 
The flowers are very pretty, and have three petals 



















































































86 


THE AQUATIC GARDEN. 


like those of the frog-bit. These are borne to the top 
of the water when ready, in order to be properly fer¬ 
tilised. As the plant is of slow growth, and tolerably 


Fig. 37- 



Water Soldier (Stratiotes aloides). 


hardy, it may advantageously be used for aquarium 
purposes, although it is not of much service for 
aerating the water. Another and a rarer British plant, 
but one which is not uncommon in the sluggish rivers 
of the east of England, is the bladder-wort ( Utricn - 









































































































BLADDER-WORT. 


87 


laria vulgaris). The submerged leaves are thread-like, 
as is so usual with those of aquatic plants, owing to 
the greater ease with which they can thus be brought 


Fig. 38 . 



Bladder-wort (Utricularia vulgaris). 


into contact with fresh supplies of water. The purple 
flower-stalks rise above the surface, and bear bloated 
looking yellozv flowers, having an upper and a lower 
lip, the former being further adorned with purplish 
veins. The common as well as the scientific name of 












88 


THE AQUATIC GARDEN. 


this pretty and interesting plant is derived from the 
presence of certain little bladders attached to the 
thread-like leaves (a). These fill with air, and buoy up 
the flower-stalks above the water. After fertilisation 
has been effected they fill with water, and thus the 
entire plant sinks so that the seeds can be ripened at 
the bottom. The bladder-wort is therefore one of 
the most interesting of all our aquatic plants, whilst 
its yellow flowers appear very prominent amidst the 
whitish or pinkish tints which our British aquatic 
flowers are usually adorned with. 

Villarsia nymphceoides is a much rarer plant than 
many of the above mentioned, but it is an exquisite 
object, and may no doubt be obtained living from 
London dealers. It is a British plant, inhabiting 
ponds as a rule, and is also found in the Thames. 
The leaves are round, and float on the top of the 
water ; whilst the largish yellow flowers are borne on 
single stalks. Trapa natans , although not a British 
plant, is easily procurable ; as it is found abundantly 
in many European streams and rivers. Its flowers 
are whitish, tinged with red, and the leaves grow in 
very elegant semi-floating clusters. We have already 
referred to the ubiquitous pond weeds (Lenina) as 
forming a fresh, green covering for small aquaria. It 
is not wise to cultivate this plant too much, as it 
gives a rather poverty-stricken look to the whole 
tank. Among other plants which are useful for 
oxygenating purposes we may mention the water 


WATER PLANTS . 



89 

star-wort ( Callitnche verna), the horn-wort (Cerato- 
phyllum denier sum ), and the pond weeds (Potanio- 
geton), of which we have several abundant species, 

Fig- 39- 


Villarsia nymphceoides. 

easily procurable. The water milfoil (Myriophyllum 
spicatum ) is a very common and graceful aquarium 
plant. Its greenish flower spike is often raised un¬ 
obtrusively above the water ; whilst its submerged 
thread-like leaves are arranged in whorls of four in 
number. This is the commonest of our British 







































































































90 


THE AQUATIC GARDEN. 


species of milfoil. The water star-wort (Callitriche 
verna) has long been extensively used in fresh-water 

Fig. 40 . 



Trapa natans. 


aquaria, not only on account of its aerating powers, 
but also because of its pretty green leaves, and the 

















































































































































































POND WEEDS\ 


91 


fondness which many aquatic animals manifest for 
employing them in several ways. The leaves are 
small and arranged in regular star-shaped or rosette- 

Fig. 41. 



Water Milfoil {Myriophyllum spicatum). 


like whorls; whilst the very simple flowers are green¬ 
ish, and easily passed over. The upper leaves may 
usually be seen floating on the water, arranged in the 
star-like form which has obtained for the plant its 
common name. Of all the pond weeds perhaps Pota - 
mogeton natans is the prettiest and most serviceable 








92 THE AQUA TIC GARDEN. 

for aquaria. The flower spikes are densely set with 
small reddish flowers, and are slightly raised above 
the surface of the water. The leaves are brownish- 


Fig. 42. 



Water Star-wort (Callitriche verna ); a, b, flowers. 


green, and very thin and prettily veined. These leaves 
are usually submerged, but few of them persistently 
floating on the top. 

Besides these aquatic plants, useful for aerating 












































































































































HORN-WORT. 


93 


che water of the aquarium, many others might be 
mentioned which could so be planted as to lend an 
additional charm to the exhibition of living animal 


Fig- 43- 



Horn-wort (Ceratophyllum demersum). 


and vegetable forms. Among these we recommend 
the sweet flag (Acorns calamus) and the bur reed 
(Spargaitium ramosum) as being not only the most 
easily procurable, but as forming the most graceful 
adjuncts. They may easily be planted within the 


























































































































94 


THE AQUATIC GARDEN. 


tank, in deepish soil or in flower-pots, and then, 
mixed with the water violet or water plantain, they 
form a varied and agreeable bordering. The singular 


Fig. 44. 



looking balls of flowers on the stems of the latter 
plant cannot fail to draw attention, whilst the elegant 
linear leaves of the sweet flag are so fragrant that 
they were once used for strewing on church floors on 
that account. 

We have endeavoured to make such suggestions 
respecting our native aquatic plants as will not only 
render them easily identifiable, but enable the amateur 
to utilise some of them for the purpose of aerating 
























BUR REED , 


95 


his aquarium. Many of them, we have either grown 
ourselves, or seen growing under conditions similar to 

Fig- 45- 



Bur Reed [Sparganium ramosum). 


those described. At the same time we have ventured 
to hint that such selections might be made as would 













































96 THE AQUATIC G A EDEN. 

convert the aquarium, if the tank be large enough, 
into an aquatic garden as well. No British plants 
have such a fragile hot-house look as our aquatic 
species, and they would therefore suit the life of 
indoors admirably, and be the means of contributing 
another element to the many surroundings which 
already make our English homes the happiest on 
the earth ! 


BRYANT'S “ THAN A TOP SIS." 


97 


CHAPTER VII. 

MOLLUSCA, INSECTS, ETC., OF THE FRESH-WATER 

AQUARIUM. 

The solitary naturalist in his search after the mani¬ 
fold living forms of life soon feels, as William Cullen 
Bryant says in “ Thanatopsis,” that 

“To him who in the love of nature holds 
Communion with her visible forms, she speaks 
A various language.” 

It is a language which gives forth no uncertain 
sound ; and, although the mystery of earthly life 
starts forth even more vividly when the student dis¬ 
covers the hourly carnage by which it can alone be 
sustained, this does not detract from an unshaken 
confidence in the wisdom and even love of the 
Almighty Power that superintends it! Mere earthly 
life is not the highest thing in the universe. The 
carelessness with which myriads are crushed, and 
even their types are lost, proclaims it to none more 
clearly than to the naturalist. We see these things 
but as in a glass darkly, yet we obtain a glimpse of 
the important fact that the life-scheme of our globe’ 
past and present, is one and indivisible, and that the 
individual members of it which perish and give place 

H 


9$ 


MOLLUSC A, INSECTS, ETC. 


to others, have no more right to complain than the 
blood-corpuscles of our body, when they are spent in 
energy and replaced by those newly formed! 

The aquarium keeper soon finds that it is neces¬ 
sary to be constantly replenishing his stock. Not 
only has he first to get something like a balance of 
animal and vegetable life, he has also to see that 
the associated animals do not breed too fast or too 
slowly. If the former, then he introduces one or two 
species which keep them down by preying upon 
them ; if the latter, he adds additional specimens. 
If all the animals of his aquaria be carnivorous and 
none herbivorous, his tank will soon be converted into 
a regular field of battle, and war will be the order of 
the day, until the combatants are reduced to the 
fabled condition of the Kilkenny cats. He has, 
therefore to copy nature in this respect, and mind 
that his aquatic pets are taken from the carnivorous 
and herbivorous classes alike, and that they are 
placed in such a relation to each other that the 
marvellous fecundation of the herbivorous group re¬ 
places the ravages made upon them by the carni¬ 
vorous. It is evident that if the herbivorous kinds 
are in the ascendant, harm will soon issue to the 
balance of life by the oxygen-yielding plants being 
devoured. Hence the importance of having both 
carnivorous and herbivorous creatures in the same 
tank if possible. 

We have dwelt at some length upon the commoner 


LIMNEAS. 


99 


Fig. 46 . 


fresh-water fishes and amphibians with which the 
ordinary aquarium may be stocked ; and now briefly 
refer to other species not belonging to these orders, 
which are equally common in all our ponds and 
tarns, and equally interesting and animated when 
transferred to the aquarium. First of all we may 
notice those commoner species of water snails, whose 
hardiness and voracity prove of great service in 
keeping down the impalpable green algae, which will 
develop even in the best managed aquarium. Of 
these none are more abundant 
than the Limnacece , and of the 
eight British species included in 
the order, perhaps the best is 
Limnea stag7ialis. It will crawl 
over the inner surface of the 
glass, and keep it as clean as 
if well dusted. Occasionally it 
may be seen floating, and then 
before it descends to the bottom 
of the tank, it utters a percep¬ 
tible sound, caused by disengag¬ 
ing the air from its pouch, which 
had kept it buoyant. This 
species is the handsomest we 
have, and the young shells are especially graceful 
and slender. Limnea auricularia is a much smaller 
shell, with a larger body-whorl, the outer lip of which 
is reflected. Although not so common as A. stag - 

H 2 



Lymnea stagnalis. 




IOO 


MOLLUSCA, INSECTS, ETC. 


nalis and L. pereger , it is far from rare. Its habits 
are very similar to L. stagnalis, except that it is 
fonder of confervoid vegetation ; and as this always 
tends to become a pest, auricularia is therefore a 
valuable addition to a fresh-water tank. Stagnalis 
has an undue preference for certain of the higher forms 


Fig. 47. Fig. 48. 



Limnea auricularia. pereger. 

of aquatic vegetation, notably Vallisneria; and if 
there be any of this plant present it will surely feed 
on it in preference to any other. When Vallisneria 
is too rank in its growth these molluscs may there¬ 
fore be employed to temporarily keep it down. 

Limnea pereger (Fig. 48) is the most abundant of all 
our native species, and, as is commonly the case with 
species that are individually numerous, it has given 
rise to at least fourteen well-marked varieties. It is 
more active in its movements than the species already 
noticed, and likes occasionally to creep out of the 
water up the stems of aquatic plants for a temporary 
breath of fresh air. It is exceedingly prolific, Dr. 
Gwyn Jeffreys stating that it lays about thirteen 


PALUDINAS. 


IOI 


hundred eggs, in numerous clusters. It is further 
distinguished from its specific brethren in not being 
confined to a purely vegetable diet, but occasionally, 
sometimes frequently, indulging in a meal off a dead 
fish, or even brother or sister. 

The genus Planorbis is not geologically older than 
Limnea , both having an antiquity which dates back 
from the early tertiary period. We have eleven 

Fig. 49. 



Planorbis Cornells. 


British species, most of which are to be met with in 
every river, canal, pond, or tarn. They vary consider¬ 
ably in size, some being scarcely larger than a pin’s 
head ; whilst Planorbis cornens often measures three- 
quarters of an inch across. All of them are herbivor¬ 
ous, and have equally the same habit, when crawling, 
of lugging their shells behind their half-extended 


102 


MOLLUSC A, INSECTS , ETC. 


bodies. Paludina is a genus geologically older than 
either of the foregoing; for the remains of certain 
species of this shell completely make up the bulk of 
the fresh-water marbles of the Wealden and Purbeck 
beds. Like most fresh-water genera, the forms have 
not greatly varied, owing, perhaps, to the similarity 
of fresh-water conditions in the most remote periods 
to those of the present time. We have two species 
extant in our ponds and rivers, of which one, Paludina 
vivipara , has always been a great favourite with 


Fig 5 1 - 



Paludina vivipara. 


aquarium keepers. As its specific name implies, it 
generally brings forth its young alive; that is to say, 
it keeps the eggs within its body until they are hatched 
there. This, however, is not always the case. The 
males are said to be usually smaller than the females. 
Both are tolerably active, and look very pretty with 
their colour bands running up the whorls of the shell. 
Both in this genus and another nearly related to it, 
which is even commoner in our ponds and streams, 



UNIOS AND ANODONS . 


103 


the Byihinia , the mouth of the shell is protected by 
an operculum , or door. Bythinia is much smaller, and 
of a more social character, so that we usually find it 
in great numbers. It also makes a good aquarium 
object, and lays its eggs in three long rows, usually 
on stones if there be any, or if not on the stems and 
leaves of plants. Bivalve shells, such as the little 
Sphcerium and Pisidiutn , may also be safely introduced. 
Their habits are active, espe¬ 
cially those of the ubiquitous 
Sphcerium lacustre , which 

crawls up and down the tank 
as if it had only one shell in¬ 
stead of two, and occasionally 

. Sphcerium corneum. 

indulges itself in a waltz, re¬ 
volving at the rate of fifteen or twenty circles a minute ! 
The tiny pea-shells ( Pisidium ) are also very abundant, 
and are extremely useful in an aquarium from their 
scavenging habit of devouring any dead and decom¬ 
posing animals, of which diet they are very fond. If 
the tank be large enough, and the soil at the bottom 
sufficiently deep, a specimen of the great swan mussel 
(Anodonta cygnea ) might be transferred. Its partly 
opened shell, showing the fringed syphons, makes it a 
very pretty and interesting object; and the student can 
witness the currents created by the ciliated tubes, by 
which fresh air and food are taken in, and effete water 
and matter carried out. A species of Unio might be 
used instead in smaller tanks, as this is a smaller 


Fig- 52 . 






K 04 MOLL use 4 , INSECTS , ETC. 

bivalve shell. The numerous eggs of both these com¬ 
mon bivalves will furnish the fish with abundant food. 

The aquatic insects that every pond usually swarms 
with, are not less attractive and interesting than the 
fishes and mollusca. Indeed, some of them surpass 
the latter in interest, on account of the life-stages 
through which they pass ; such as the larvae of the 
dragon-flies, caddis-worms, water beetles, &c. What 
could be more astonishing than the fact that the early 
life of many aerial and winged insects is passed in 
water, under conditions which are as contrasted as 
possible with those which affect them in the adult 
condition ? Even in their individual life-histories these 
creatures furnish a sufficient answer to those who 
demand “missing links! !> And it is not a little 
suggestive that the insect orders which appeared first, 
during the carboniferous epoch, were those whose 
members now pass through less differentiated larval 
stages than those which were introduced later on, such 
as the butterflies (Lepidopterd) and Neuroptera. More¬ 
over, the Orthoptera (a fossil species of which is the 
first to appear of all known kinds of insects) is an 
order which perhaps even yet furnishes a larger 
number of species whose lives are passed under 
aquatic as well as aerial conditions, than any others. 
Even the caddis-worms, which are the larvae of in¬ 
sects in some respects nearly related to the Lepi- 
doptera, have an enormous geological antiquity. We 
have seen limestone beds 5 and 6 feet thick, com- 


YOUNG DRAGON-FLIES. 


105 


posed of their shelly tubes alone, in central France. 
These are of miocene age. 

The young of the dragon-flies do not assume a 
quiescent attitude when they pass into the pupa stage. 
On the contrary, they are more active and voracious 
than ever. Any old pond or tarn will yield these 
insects, and they may afterwards be watched going 
through those evolutions which eventually end in the 
insect leaving the water and climbing up some water 
plant so that it can shake off its old clothes, and enter 
upon a winged existence. Perhaps, when living in 
the water, the larvae of the dragon-fly are never more 

Fi g- 53- 



Larvae of Dyticus. 


actively engaged than when chasing the water fleas 
( Daphnia ). The larva of the Dyticus is still more 
ravenous, and is so courageous and fierce, that it has 
earned the popular name of the “ water devil.” It 
will attack sticklebacks, minnows, the larvae of dragon¬ 
flies and water scorpions ; whilst the poor tadpoles 
are sacrificed by scores to its hungry maw. Nay, 
so fearfully are they afflicted with the sensation of 
hunger that they will fall on each other, if nothing 


io6 


MOLLUSC A, INSECTS , ETC. 



Fig. 54- 


else be present. They frequently cast their skins, 
which may be mounted as microscopical objects; 

showing the spiracles, or breath¬ 
ing mouths, peculiarly adapted 
to water. So fierce are these 
common objects that they will 
readily seize and hold on to 
a stick with whose end they 
have been taunted. The Dyticus 
marginalis varies so consider¬ 
ably in the appearance of the 
sexes that they are not unfre- 
quently mistaken for two dif¬ 
ferent species of beetles. Their 

Water Scorpion attacked by hind-legs are peculiarly adapted 
Larva of Dyticus. or- j r 

for swimming, owing to their 


Fig. 55- 


Fig. 56- 




Male of Dyticus marginalis. 


Female of Dyticus marginalis. 


being flattened out into oar-like expansions. The 
fully-developed insect bears out the character it ob- 


















































WATER BEETLES. 


107 


tained in its larval stages as the “ water devil ” on 
account of its voracity and destructiveness. Indeed, 
it is a very difficult matter to keep the larvae, unless 
we separate them. The fully-developed Dyticas leaves 
the water during the night, in the summer months, 
so that if the top of the aquarium be not closed, its 
owner may be somewhat astonished at seeing some 
of its aquatic inhabitants leaving it to dash themselves 
against the gas-globes ! 

Fig. 57- 



Great Aquatic Beetle (Hydrophilus piceus). 


Hydrophilus or Hydrous piceus , or great aquatic 
beetle, is the largest of our British species. It is in 
wondrous contrast with the Dyticus in its habits, 
for it is extremely inoffensive, and therefore well 
suited to a fresh-water aquarium. Indeed, the full- 
grown insect not unfrequently falls a victim to the 


108 MOLLUSC A, INSECTS , ETC. 

savageness of the larva of Dytictis. It is interesting 
to watch the Hydrous lay its eggs, in a kind of silken 
cocoon, spun by the mother. In this cocoon the eggs 
float about until they are hatched. Curiously enough 
this beetle swims by alternate movements of its legs. 

The smooth surface of most ponds may often be 
seen streaked by the mazy paths of the whirligig 
beetles ( Gyrinidce ). Other and not uncommon water 
beetles are the Colymbetes, related to the Dyticus. 

The Hemiptera , or water bugs, are represented in 
most ponds by the water scorpion ( Nepa ), and water 
boatmen. The former (which is engraved in Fig. 54 
as being attacked by a Dyticus larva) is itself so 
voracious as to have obtained the popular name it 


Fig. 58 . Fig. 60 . 



Colymbetes. ( Notonecta ). 


bears. It will float in the summer sun for hours at a 
time, in a complete invert attitude; but soon and 
rapidly moves when disturbed. One or two of these 
insects may be safely placed in a large tank, especially 
where there are too many tadpoles, as they keep the 
latter down by feeding on them. The water boatmen 
(.Notonecta) are also hemipterous insects, deriving their 
Latin generic name from their habit of swimming on 


CADDIS-WORMS. 


109 


their sides or backs. They are very active, inoffensive, 
and interesting aquarium objects. 

Fig. 62. 



4, 5, 6. Various species of Caddis-worms ( Phryganea ). 
3. Larva when taken out of case. 

1 and 2. Perfectly developed insects. 


The various species of caddis-worms which haunt 
our streams, ponds, and lakes belong to the order 















































































no 


MOLLUSCA , INSECTS , £7T. 


Phryganeidce. There are a great many of them, and 
the larvae of each have usually a different plan of con¬ 
structing their well-known tubes, by which they may 
be identified. Some select minute shells of a species 
of Planorbis or Pisidium ; others use grains of sand. 
The genus Limnephilus prefers pieces of rush or other 
aquatic weeds. But all of them are interesting, and 


Fig. 63. 



Limnephilus flavicornis. 


Fig. 64. 



Larvse of Phryganea grandis. 


Fig. 65. 


Fig. 66. 



Limnephilus 

rhombicus. 



Caddis-worm pro¬ 
jecting its head out of 
tube. 


seem to be perfectly aware that they are regarded as 
choice and dainty bits by other larger and more active 
water animals. All of them hold on to the interiors 
of their frail defences by means of a series of hooks, 
so that it is somewhat difficult to drag them out 
forcibly. Before they pass into the quiescent state, 
previous to changing into their image condition, they 
protect themselves by making gratings at the ends of 
their tubes. The insects into which these larvae even- 


WATER SPIDER. 


Ill 


tually pass, in many respects (notably in their having 
scales on their wings) resemble butterflies and moths. 

The larvae of another insect, belonging to the 
Ephemera , is usually very abundant in ponds. It is 
shown in its natural size at b , Fig. 67, as well as 


Fig. 67. 



Larvae of Ephemera. 


enlarged, to indicate the breathing leaflets along the 
sides of the body. 

Nor should we forget the exceedingly interesting 
water spider, not only because its habits depart so 
extremely from those of its kind, but also on account 
of its prettiness and intelligence. This species (Ar- 
gyoneta aquaticci) is not uncommon. In the water it 
looks as if its body were covered with a film of 
quicksilver. This is in reality a film of air which it 






































112 


MOLLUSCA, INSECTS, ETC. 


entangles on the surface and carries below, so as to 
fill the diving-bell-like nest it has spun with it, and 
which is air-tight This nest is filled by successive 
journeys of the spider to the surface, to store up the 
air for subsequent breathing. These air-nests may 
be seen in most ponds, especially where there is an 
abundance of Anacharis and water-crowfoot leaves. 
There are several species of the order Arachnidce 
which live in water, but they are usually of the kind 
we call “ticks.” Some of them pass through very 
interesting metamorphoses, being parasitic on plants 
and insects alternately before they attain their fully 
developed condition. 

It will be seen that the objects required for stocking 
ordinary fresh-water tanks are not difficult to find ; 
and, if proper precaution as to the habits and voracity 
of the different kinds be taken, there need be little 
fear as to ultimate and continued success. Every 
aquarium, large or small, ought to be as perfect an 
imitation of natural conditions as possible, and suc¬ 
cess always depends on the degree to which this is 
carried out. 


MICROSCOPIC RESEARCH. 


US 


CHAPTER VIII. 

THE AQUARIUM AS A NURSERY FOR THE 

MICROSCOPE. 

To those who keep aquaria for the sake, not merely 
of being amused, but of learning the higher lessons 
which animated nature is ever so ready to teach, both 
fresh-water and marine parlour-aquaria may easily 
be converted into nurseries for microscopic research. 
Here may be reared with the utmost ease thousands 
of minute forms of life, whose ephemeral history of 
various conditions may be actually seen enacted upon 
the stage of the microscope. Human eyes can thus 
look down upon and witness the evolutions of these 
lower forms of life, just as it is possible other eyes 
look down upon our own terrestial career. 

The fresh-water tank especially is worth supporting, 
even for the sake of its microscopical animals and 
plants alone. Mere littleness does not detract from 
the interest of their microscopical study, but rather 
throws a romantic glow about it. By the true natu¬ 
ralist magnitude is not taken specially into account, 
nor is minuteness of size regarded as in itself a sign 
of low organisation. It is true that most of the lower 
forms of life are microscopic, but this is because it is 


I 


i 14 A NURSERY FOR THE MICROSCOPE. 


an advantage to them in the peculiar conditions 
by which they are surrounded. Not unfrequently 
their small size is more than compensated for by the 
enormous rapidity with which individuals are pro¬ 
duced. Many of the lowest types of vegetable life 
with which every tarn, pond, and stream is crowded, 
and which may be kept with the utmost ease ready 
for inspection in the aquarium, are single-celled. But 
these single cells are constantly splitting into two 
parts, as in the Desmids and the Diatoms , each of 
which becomes a new individual, and goes through 
the same mysterious self-division. The main differ¬ 
ence between these peculiar objects and vegetable 
species of a higher organisation and greater magnitude 
„ seems to us to consist in the fact that in the former 
the cells are detached as fast as they are formed, 
whereas in the latter they adhere together, and thus 
produce objects of large volume. This is proved by 
the fact that all species of desmids and diatoms are 
not single cells. Not unfrequently we find them living 
in colonies, either for the whole or part of their lives. 

Few objects are prettier than the microscopic plants 
we are now referring to. Seen by the naked eye their 
presence is perhaps only revealed by the green film 
covering the inside of the glass, to which aquarium 
keepers who are not microscopists strongly object. 
Desmids and diatoms often cover the stems and 
leaves of aquatic plants with a greenish or olive- 
coloured slime, such as Hyalotlteca dissiliens (Fig. 69). 


DESMIDS. 


115 

The sliminess in which many of the desmids are 
invested usually serves the purpose of keeping the 
loosely aggregated cells together, as in the species 
just mentioned, whose generic name is derived from 
this glassy sheath. But although these colonies of 


Fig. 69. 



Hyalotheca dissiliens. 


Fig. 70. 


Euastrum ob Ion gum. (Front view) X 250. 


desmids are far from uncommon, they are not so 
abundant as the single-celled species. The latter 
may nearly always be seen in the act of dividing 
themselves into two halves—their only method of 
reproduction. 

Among these the genera Cosmarium , Micrasterias , 
Closterium , and Euastrum are usually abundant, and 
the student may readily obtain and keep them 
















il6 A NURSERY FOR THE MICROSCOPE. 


for examination in his glass tank. As a rule, 
however, the lower vegetable forms thrive better in 



X 250. Closterium slriolatum x 250. 

small tanks than in large ones. The desmids are 
purely fresh-water algae, and may readily be dis¬ 
tinguished from the diatoms to which they are so 








DIA TOMS. 


117 


nearly allied, by the fact that they are always of a 
light pea-green colour, whereas diatoms are usually 
of a dull olive-brown. Again, diatoms are found in 
fresh, brackish, and salt water alike, whereas we have 
seen that the desmids are confined to fresh water. 
Another most important difference is the fact that 
diatoms have the power (which desmids have not) of 
secreting a siliceous or glassy film on their exterior, 
like that which coats the outside of straw. This glassy 
film remains perfect after the diatom is dead, and is 
called the “frustule.” It is divided into two parts, 
like the body and lid of a pill-box, so that the same 
species has a very different appearance according to 
the side which is looked at. These glassy cases or 
frustules are indestructible, and often accumulate to 
an extraordinary depth. They form a considerable 
part of the black mud laid bare at low water in tidal 
rivers or estuaries—they compose the greater part 
of similar material in our ponds and ditches. They 
will accumulate on the bottom of an old aquarium, 
where they may always be obtained. A little and 
patient treatment with hydrochloric, sulphuric, and 
nitric acids, to get rid of the soluble organic matter, 
at length displays these glassy sheaths or frustules in 
all their beauty, adorned with dot and line and curve, 
in the most extravagant and even luscious style of 
ornamentation. We have frequently thought that 
these diatom ornamentations might be studied to 
some purpose by jewellers and others interested in 


IIS A NURSERY FOR THE MICROSCOPE 

developing new designs. We give an illustration of 
the glassy frustule of a British species of Isthmia , 
magnified four hundred times, to prove that the 


Fig. 75 - 



Pinnularia major. Pleurosigma formosum. Navicula didyma. 


application of a higher microscopic power only brings 
out the beauty of these forms into more prominent 
relief than otherwise. In this figure the student will 





























STALKED DIATOMS. 


119 


also see the mode of attachment of the lower angle 
of the frustule to the one beneath, by a kind of 
gelatinous cushion. It is among the marine species 


Fig. 77. 



Stauroneis. 


Fig. 78. 



Isthmia enervis. 


of diatoms, perhaps, that we are to look for those 
possessing the greatest beauty, as in Figs 79 and 80 
( Cocconeis ). Among the commonest of our native 














120 A NURSERY FOR THE MICROSCOPE. 


species are Pinnularia , Stauroneis , Pleurosigma , and 
Navicula. The latter is especially abundant, and 
may be seen moving about—a spectral craft, with¬ 
out oars or crew—amid the tangled mass of living 


Fig. 80. 


Fif*. 70 . 



Cocconeis major . 


and decomposing vegetation to be seen in a drop 
of water taken from the bottom of the tank ! The 
boat-like outline (whence the name of Navicula , 
and others which some of the genera bear) is then 
seen to be admirably adapted to move in and out 
of such interstices. It is indeed most instructive 
to see these diatoms going this way and that, as 
if gifted with sense, backing in and out, turning 
one way and another, as if they possessed volition. 
And yet we know they are merely very lowly orga¬ 
nised cells. Division takes place by one half of the 
glassy shell, with its contents, separating from the 
other, just as we should take the lid off a full pill-box. 












STALKED DIATOMS. 


121 


The enclosed protoplasm soon adds a new film of 
silica to the naked surface, and thus a new diatom is 
born. Many of the diatoms, like the desmids, live 
either part or the whole of their lives in colonies, as 

Fig. 81. 



Licomophora flabellata. 

for instance Licmophora (Fig. 81). This is a marine 
species, and may be found in rock-pools, where it is 
readily identified by its resembling a golden wool, 
shining like spun glass when transferred to the col- 












122 A NURSERY FOR THE MICROSCOPE. 


lecting bottle. We have magnified one of the fans to 
show how closely the individual diatoms are packed on 
the summit of the jelly-like or protoplasmic stalk. 

Fig. 82. 



Fan of Licomophora. 


Among the lower species of animal life which may 
be transferred from the pond to the aquarium are 
the Amcebas, rotifers, fresh-water polyzoa, hydras, 
water fleas, cyclops, infusoria, &c. The fresh-water 
sponge (Spongilla jluviatilis ), although common in 

















FRESH-WATER SPONGES. 


123 


clear streams and ponds, is difficult to transfer to 
the aquarium without damage. It has been effected, 
however, and Mr. F. Meggy gave a description in 


Fig- 83. 



an eariy volume of ‘ Science Gossip,’ of a successful 
experiment in acclimatising this animal. If only 
domesticated its development becomes one of the 
most interesting of microscopical investigations. The 
young are seen thrown off as gemmules, and the 
greenish-yellow gelatinous flesh, which constitutes the 
true sponge, is seen investing the spicules—or rather, 
the latter are imbedded in the sarcode or flesh. The 
shapes of these spicules are due to an organic crystal¬ 
lisation, and although admirably symmetrical in form, 









124 A NURSERY FOR THE MICROSCOPE. 

are no more mysterious than the crystallographic 
shapes of minerals. The Amoeba is a still commoner 
object, which will find its way into the aquarium 
whether we will or no. It is a minute, gelatinous speck, 


Fig 84. 



Amoeba villosa, with diatoms, &c., in its interior. 

possessing the power of protruding any portion of its 
body in any direction at will. The sarcode of all 
sponges is usually regarded as made up of a colony of 
such amoeboid forms. The true Amceba never secretes 
spicules, although we may frequently see the frustules 
of diatoms imbedded in its mass (Fig. 84). These, 
however, are the objects on which it feeds, and over 
which it has the power of gradually pouring its 
own flesh until they are enclosed, and await assimila¬ 
tion. Then the solid parts are as gradually passed to 
the outside and extruded. The fresh-water hydras are 
most interesting aquarium objects. We have two, if 
not three species, one of which, Hydra vulgaris , is 
very common. They are each about one-eighth of an 


HYDRAS. 


125 


inch in length, and may be seen suspending them¬ 
selves from the under side of the leaves of the duck¬ 
weed (Lemna), or the thread-like leaves of the water 


Fig. 85 



Hydra viridis . 


crowfoot (Fig. 85). Few fresh-water objects have been 
more studied, since the first experiments upon them 
by Trembley a long time ago. When watched with 
a one-inch power it is surprising what a store of 
perpetual interest is afforded by them. We can then 
witness the vegetable process of budding , in which the 
lower animals are on a par with the higher vege¬ 
tables ; we can see the sperm-cells discharged from 
the tubercles, and notice the young developing 
through the various stages of growth, until they 
attain the parental size and shape. 

Minute though these animal and vegetable forms 

















126 A NURSERY FOR THE MICROSCOPE, 

Fig. 86. 



Showing Hydra magnified ; and at a prominences, which subsequently 
burst as at b , and thence issue spermatozoa. 







DEVELOPMENT OF HYDRA. 


12 7 


of life are, they are as admirably adjusted one group 
to the other, as the higher animals are to feed 
on and keep down the higher plants. Moreover 

Fig. 87. Fig. 88. 




First stage of development of Second stage of development 
Hydra. of Hydra. 

there is the same kind of dependence on each other’s 
needs. The microscopic plants, such as desmids and 
diatoms, give out just the oxygen which amcebas, 
hydras, or rotifers require. Again, we find amongst 
the lower types of animal life the same broad 
differentiations which stand out so visibly among 
the higher, of carnivorous and herbivorous. Death 
is as much the law of the life of the microscopically 
small as it is of such creatures as the tiger and 
the antelope. 

The rotiferal animalcules may be obtained and 
kept in any abundance. Some of them, as for instance 
the Melicerta , will be found attached to the various 
small leaves of plants. These are usually deno¬ 
minated “stalked" rotifers. All around it the Meli¬ 
certa builds up a caddis-worm-like case, composed 
of pellets of rejected or excreted food. With 



128 A NURSERY FOR THE MICROSCOPE. 


a half-inch objective we may see the currents 
produced by the cilia of the disk, whose rapid, 
successive movement gives that impression of the 

Fig. 89. 



Disk of Melieerta , showing currents by cilia, and pelleted tube 

(greatly magnified). 

revolutions of a cog-wheel which has procured for 
these creatures the name of Rotifers , or “wheel- 
animalcules.” Even more beautiful than the Melicerta 
is the “ crown animalcule ” (Stephanoceros Eickornii), 
Fig. 90. It may be found in many ponds and rivers, 
and easily transferred to the tank. Its five arms 


CROWN ANIMALCULE , 


129 


are beautifully feathered 
with cilia, and are 
capable of being folded 
up like the petals of a 
tulip. All the active 
functions of life may 
be seen in operation 
through the transparent, 
gelatinous envelope in 
which this creature is 
enclosed. Although 
fixed to one place, its 
maelstrom-like currents 
swirl into its fate-like 
grasp crowds of active 
little infusoria. The 
power of sudden con¬ 
tractility possessed by 
all these sessile rotifers 
is very remarkable. As 
you witness the with¬ 
drawal or collapse of 
the ciliated arms you 
are almost startled, and 
dart back from the tube 
of the microscope which 
is revealing the fact, as 
if a gun had been fired 
near you ! Even some of 


Fig. 90. 



The Crown Animalcule ( Stephano• 
ceros eichornii). 

K 



























130 A NURSERY FOR THE MICROSCOPE . 


the infusorians on which these rotifers feed, have their 
stalked and free conditions, as in Vorticella , Epistylis , 

Fig. 91. 
a 



Epistylis , showing stalked individuals at a to d, and free individuals 
at f andg; h , individuals showing cilia. 

&c. The latter often grows so thickly on water fleas 
and cyclops, as actually to impede their movements in 





ROTIFERS. 


131 

the water ; and so we find them masked with a forest 
of Epistylis, just as marine crabs often are with sertula- 
rians. The free-swimming rotifers are very active in 
their habits, although we may witness them as long 
as we like, quietly grazing among the microscopic 
thickets of fresh-water algae in which they most love 
to disport. The play of their wheel-like crowns is 
exceedingly graceful, whilst their bodies are usually 
so transparent that we can see all the internal move¬ 
ments and processes as plainly as if they were con¬ 
structed of glass. As its name implies, Rotifer vul¬ 
garis is very common, and the student cannot fail 

Fig. 92. 



Rotifer vulgaris. 


to find it in his fresh-water tank. When removed by 
means of the common dipping-tube, to the slide, and 
placed under the microscope, it behaves as if it had 
not been transferred to new quarters, and evidently 
seems to know that the enormous quantity of force 
which is given off in its active habits, requires to be 
replaced by a corresponding quantity of food. Hence 
the great business of its life seems to be feeding. The 
rotifer is not a gourmand; everything seems to be fish 

K 2 




132 A NURSERY FOR THE MICROSCOPE . 


that is swept into its living net. You see one bit of 
semi-decomposing vegetation after another descend 
into its funnel-shaped gullet—now an Amoeba, and 
now an unfortunate infusorian, terminates its career 
in the same trap. 

Fig. 93- 



Rotifer sucking in an Amoeba, by means of the current produced by 

the cilia. 

Not less, but infinitely more interesting when care¬ 
fully observed, are the habits of another rarer group 
of fresh-water animalcules called Polyzoans. They 
are nearly related to sea-mats, found so plentifully 


FRESH-IVATER POLYZOA . 


133 


Fig. 94. 



Fresh-water Polyzoon (Lophopus crystallina ) (magnified). 

on our coasts, and are somewhat out of their sphere 
in fresh water, salt being that in which, as a 








































































134 A NURSERY FOR THE MICROSCOPE . 


Fig. 95 - 



Plumatella repens investing stem of 
weed (magnified). 


family, this group is best 
distributed. Neverthe¬ 
less, we have several 
British species of poly- 
zoa, which are not un¬ 
common. They are well 
worth finding and trans¬ 
ferring to the aquarium, 
for it is impossible for 
any other group of mi¬ 
nute animals to afford 
the same degree of plea¬ 
sure, so lovely are the 
shape and movements of 
these creatures. They 
are much more highly 
organised than rotifers, 
and consequently per¬ 
form more functions. We 
always find them at- 
tached to the stems or 
thread-like leaves of 
water plants. Of our 
British genera Lophopus 
and Plwnatella are the 
commonest (Figs. 94 and 
95). In the figure of 
the former we have the 


region 


of the mouth 









WATER FLEAS. 


135 


shown at a , the oesophagus at b , the stomach at c, the 
intestines at d y the muscles at e> the mouth at hh> 
the withdrawn tentacles at i, the lophophore , or 
“ crest-bearer/’ which is covered with cilia, at m. The 
same kind of horse-shoe shaped lophophore, or crest, 
surrounds the mouth of Plumatella . 


Fig. 96. 



Cyclops , showing female with egg-bags ; the young, and a single- 

jointed antenna. 

Cyclops and water fleas {Daphnia) ought to be en¬ 
couraged in every fresh-water aquarium. Their food 
consists chiefly of decomposing aquatic vegetation, 
desmids, &c., whilst their own wonderful powers 
of reproduction will always people the water with 
living food for the higher animals. Most fishes and 
amphibians live to a very great extent upon these 
creatures. Cyclops (Fig. 96) is a very common 
aquatic object, and the female may be seen with the 
naked eye. So prolific is she that it is stated she 






1 36 A NURSERY FOR THE MICROSCOPE. 


would be the progenitor of four millions and a quarter 
of young in twelve months, if undisturbed. Her 
motherly devotion is seen in the way in which she 
swims about with her purse-like egg-bags trailing 
behind her. The young are ludicrous objects, with 
nothing of the gracefulness of their parents. They 
have a crab-like form, which indicates their crustacean 
belongings, and they move about in the most cranky, 
jerky manner it is possible to conceive, like the big 
seconds finger of a large clock. 

Both Cyclops and water fleas ( Daphnia ) have such 
a transparent skin that we can see their internal 
organs, and watch them fulfilling their several func¬ 
tions. As is the case in most insects, the female is 
larger in size than the male. These creatures are 
a very old race, for we find them fossilised in carbo¬ 
niferous shales in such prodigious numbers that we 
feel assured they must have bred as plentifully 
millions of years ago as they do now, when they 
not unfrequently darken the water of our ponds with 
their countless crowds. During entire geological 
periods they have been the food-stock of fresh-water 
and marine fishes alike, and we find them adapted 
to all conditions of aquatic life. 

Space forbids us to notice other common micro¬ 
scopic objects which may be readily introduced into 
the parlour tank, and kept ready for observation. 
They might thus while away many an hour of gloom 
and perchance of sickness or sorrow; and cannot fail 
to add another element of interest to aquarium keep- 


WA TER FLEAS. 


137 


ing. The two powers which move the human world, 
love and hunger, seem to reign quite as predominantly 


Fig. 97. 



Fig. 98. 



Water flea (Daphnia palex) 
male, enlarged to correspond¬ 
ing proportion as Fig. 97. 


Water flea (.Daphnia pulex) female, magnified 
to show internal organs. The small figure en¬ 
closed within a circle shows the natural size. 


among animalcules. It is not “live and let live,” 
however, which is their rule ; but “ might is right! ” 























1 38 A NURSERY FOR THE MICROSCOPE . 

The weakest are constantly going to the wall, with 
a vigour in which there is no room left for pity, except 
in the soul of the beholder! May not that be the case 
with ourselves, and the Great Power whose wisdom 
has called us and them alike into existence, to fulfil 
some inscrutable but all-wise purpose of his own ? 


PARLOUR AQUARIA . 


139 


CHAPTER IX. 

MARINE AQUARIA FOR ROOMS. SEA-WEEDS 

FOR AQUARIA. 

THERE are undoubtedly greater difficulties attending 
the healthy maintenance of small marine tanks in 
rooms than fresh-water ones; but some of these 
difficulties vanish before a little common-sense treat¬ 
ment and knowledge of the habits of the creatures we 
endeavour to keep. As a rule the marine aquaria 
kept in houses are on too small a scale, and there is 
the unconquerable tendency on the part of their owners 
of putting as many objects in them as they possibly 
can. There is really no reason why small marine tanks 
should not be kept in a good condition for years, 
provided they are attended to, say as we should 
attend to poultry, rabbits, guinea-pigs, canaries, or 
any other pets we are rearing under semi-artificial 
conditions. If these are neglected, everybody knows 
the consequences ; and we cannot expect that healthy 
aquaria can be maintained and neglected at the same 
time. Indeed, considering how altered are the circum¬ 
stances under which they live, the wonder is that the 
inhabitants of aquaria give so little trouble. 

In constructing small tanks to hold sea water the 


HO MARINE AQUARIA FOR ROOMS. 

same cement may be used as is mentioned when 
speaking of fresh-water aquaria. The glass sides 
may be secured by using Collin’s patent elastic 
and marine glue. Rockwork is more indispensable 
in a tank of this kind than it would be in fresh water, 
where it is often in the way, rather than otherwise. 
It ought to be built up in the middle, unless there are 
reasons to the contrary. Pumice-stone, pieces of mica 


Fig. 99. 



Octagonal Marine Table Tank. 


schist, the slag obtainable from brick-kilns, and oyster 
shells covered with serpula, are the best kinds of ma¬ 
terial, inasmuch as they do not give off anything that 
will affect the water. The rough surfaces of the pumice- 
stone and mica soon get greened over with minute and 
semi-developed algae, and then look very pretty. The 
rockwork ought to be built in arches and caverns, so 
that the inhabitants may find shelter from the glare 
of the too strong light, and cool spots where they can 
repose. Nearly all the Crustacea shun the light when 



































SMALL MARINE TANKS. 141 

they are about to moult, and such caverns and grottos 
are to them very necessary. Very fine, well washed 
sea or river sand should be strewn on the bottom of 
the marine tank, and the depth ought to be adjusted 
to the creatures it is intended to keep. If marine 
worms, such as Sabella and Terebella , and even some 
Crustacea, it should be of considerable thickness; but 
always with fine shingle mixed with it, for these 
creatures love to burrow in it. Shrimps take great 
pleasure in dusting themselves with the fine sand, 
descending into it and throwing it about them much 
after the manner of birds. 

As only few kinds of sea-weeds can be successfully 
grown in small aquaria, it follows that aeration or 
oxydization of the water has to be compassed by 
artificial means. The sea-lettuce (Ulva latissima), 
Fig. 100, is believed to give off more oxygen than any 
other marine plant, and is well acted upon by the sun 
in clear, shallow water, insomuch that we may often 
see its bright green surface silvered over with minute 
bubbles of oxygen. The best way to transfer sea¬ 
weeds is to find small specimens rooted to pebbles or 
rock, and bring them as they are thus found, taking 
care not to break or bruise them, otherwise they will 
slough. Cladophora is a sea-weed which grows readily, 
and when its thread-like fronds are expanded, it 
has a very pretty appearance. If the student is 
not perplexed by a little extra trouble, there will 
be little difficulty in growing other sea-weeds; 


142 


MARINE A2UARIA FOR ROOMS. 


but he must remember they are by no means so 
easily reared as fresh-water plants, and when they 

Fig. 100. 



Sea-Lettuce (Ulva latissima ). 


sicken and die they taint the water, and give off 
a noisome smell. We have seen aquaria, however, 


SEA-WEEDS . 


143 


in which both red and green sea-weeds were growing 
and looking as bright as a garden parterre. To 
bring these somewhat capricious plants up to this 
pitch is well worth the trouble. In this way it is not 


Fig. 101. 



Callithamnion. 


impossible to have a marine garden of such lowly 
organized “ flowers of the sea/' as they have been 
somewhat sentimentally termed. The red sea-weeds 
should be planted in the darker places, for they shun 
the light more than the green and the olive-coloured, 
most of which, on the contrary, seek it. The best 
sea-weeds are the smallest. The student ought by 
no means to attempt the larger wracks, as they give 




J 44 MAXINE AQUARIA FOR ROOMS . 

off a good deal of mucus when sickly, and poison the 
water. The following species are the prettiest, and offer 

Fig. 102. 


Delesseria sanguined. 

Fig. 103. 


Plocamium plumosum. 

a certain variety of colour and tint, which make an 
aquarium look very pretty: Ulva, Callithamnion , 















RED AND GREEN SEA-WEEDS 


US 


Cladophora rupestris or arcta, Bryopsis plumosa , Grip - 
fithsia setacea, Corallina officinalis , Enteromorpha in- 
testinalis i Ceramium rubrum , Rhodymenia palmata, 
Delesseria sanguinea , Padina pavonia , Plocamium 
coccineum , &c. Corallina requires a good deal of 
lime, for it will cover the rock on which it is growing 


Fig. 104. 



Padina pavonia. 


with a him of pinkish-white limey matter. If the 
tanks be large enough the small wrack (Fucus canali- 
culatus) and the carageen or “ Irish moss ” ( Chondrus 
crispus ) may be grown. The latter takes to its ground 
very readily, and is really a very pretty plant, liable 
to assume different tints according to its surroundings. 
The fructification of the small wrack is a very interest¬ 
ing performance, and may be studied in the aquarium 
if this species can be induced to grow. We have seen 

L 




I 4 & MARINE AQUARIA FOR ROOMS 

another not uncommon sea-weed (Halidrys siliquosa) 
grown in tolerably large marine tanks, and looking 
both healthy and attractive. The Zostera marina — 
a true flowering plant, and not a sea-weed—may even 
be grown where the tank is large enough. This is 
undoubtedly a most useful plant for giving off oxygen. 
Mr. Shirley Hibberd recommends Codium tomentosum, 


Fig. 106. 



Corallina officinalis 



not only on account of its growing easily, but because 
it is a favourite food-plant for many mollusca, &c. 
For it should be remembered that if certain animals, 
hereafter to be mentioned, are introduced, they will 
feed on many of the sea-weeds ; so that the latter 
have to serve the double purpose of aeration and 






RED SEA-WEEDS. 


147 


provision. Indeed, there can be little doubt that 
one of the “ stock ” kinds of food for many marine 
creatures consists of the zoospores, &c., of sea-weeds. 

Fig. 107. 



Rhodymenia palmata. 


Nitophyllum is another genus of beautiful green sea¬ 
weeds, readily obtained in true rock-pools. Autumn is 
the best time for introducing sea-weeds, as the spores 

L 2 















































148 


MARINE AQUARIA FOR ROOMS. 


are then given off, and next spring many of these 
may sprout into a healthy vegetation.* 

It should be remembered, however, that in a parlour 
tank, small or large, there will not be sufficient aeration 


Fig. 108. 



4 ‘ Irish Moss ” (Chondrus crisp us). 


produced by sea-weeds, unless the number of animals 
is very few. To assist in this most important end, a 
fountain, constructed like that in Fig. 1, may be ad¬ 
vantageously used. Some people content themselves 

* In the Crystal Palace and other aquaria, some species of sea¬ 
weeds have spontaneously made their appearance from spores. Mr. 
Saville-Kent thinks that the larger sea-weeds might be grown where 
the rapid circulation of the water produces a strong current. 





PUTRID WATER. 


149 


with using a syringe every now and then, just to 
mechanically entangle air in the injected water. There 
is no harm whatever in this method, but we prefer the 
above fountain. In the huge tanks of our public 
aquaria the sea water is aerated entirely by various 
mechanical processes, which will be shortly described. 


Fig. 109. 



Small Wrack ( Fuchs canaliculatus). a , Spore-case. 


No paint should be used, in the interior, at any rate, 
of any aquarium; and if it can be avoided on the 
outside it is all the better, as the presence of paint 
seems to cause annoyance and sickness to all kinds of 
animals. When the sea water becomes putrid it is for 
want of oxygenation ; and a little artificial oxygen 



15 ° MARINE AQUARIA FOR ROOMS. 

gas, forced into it from a bladder, to the mouth of 
which a clean, long tobacco pipe has been fastened, 
so that it can reach the bottom, might, under some 
conditions, soon put it to rights. 


Fig. iio. 



Halidrys siliquosa (nat. size). 


A most useful and beautiful animal is the Ormer 
(Haliotis tuberculata :), or “Venus’s ear,” as it is some¬ 
times called. This univalve is common along the 
shores of the Channel Islands. In the aquarium it 
is as good as a natural scrubbing-brush for keeping 
the sides, &c., clean ; whilst it is equally useful in 



NA TURAL SC A VENGERS. 151 

devouring decaying vegetation. The common peri¬ 
winkle (Littorina littored) is another good scavenger, 

Fig hi. 



Ormer (Haliotis tuberculata). 


Fig. 112. 



Limpet (Patella vulgaris ). 

but a voracious feeder. The limpet (Patella vul¬ 
garis) doer> its work more slowly, but effectively, and 






















152 


MARINE AQUARIA FOR ROOMS. 


cleans the glass and rocky surfaces. Like the peri¬ 
winkle, it will often crawl above the level of the water. 

Mr. W. R. Hughes recommends Mr. Edwards’s 
plan of having a parlour tank with a sloped back, and 
we thoroughly agree with him that this is by far 
the best arrangement. It has the merit of enabling 
the animals to adjust themselves from the shal¬ 
lowest to the deepest parts according as their habits 
require ; and offers a minimum space for the recep¬ 
tion of the rays of sunlight. Over this sloping 
back, or bottom, rockwork is to be arranged, as 
already described. The sloping bottom may be per¬ 
forated, so that the tank is divided equally into a dark 
and a light chamber. Such an arrangement sets up a 

Fig. 113. 



Section of Slope-back Tank, showing Dark Chamber. 


slow, natural circulation, whilst it prevents the undue 
development of the spores of algae. Another means 
of promoting circulation is that of having syphons, 
which may be made to gently pour in the tank a 
fine stream of water from a jar placed above. If 
the current is made to flow a few inches through the 

















SLOPE-BACKED TANKS. 


153 


air, it will mechanically entangle some of it and 
thus convey it to where it is required. But the 
ingenuity of a really careful aquarium-keeper will 
soon suggest to him various simple means of this 
kind, by which additional aeration can be obtained 
if required. The water referred to is of course taken 
from the tank into which it is made to run. In the 
volume of ‘ Science Gossip,’ for 1870, the following 
contrivance is mentioned : “ I had been in the habit 
of drawing off the water to a certain extent daily, but 
in time it became apparent, as my interest began 
to flag (as it sometimes will) that this was a somewhat 
fatiguing process, and therefore one that was likely 
to be forgotten for a day, thus greatly deteriorating 
the condition of the water. In order, therefore, to 
make the tidal arrangement as self-acting as possible, 
I added the following : At the level of high-water 
mark I made a hole in the slate back of my tank ; 
through this I inserted a glass tube (which may be 
made to fit completely water-tight by placing over it 
a piece of indiarubber tubing). This tube inside is 
bent down like a syphon to the level of low water 
in the tank ; on the outside it communicates with 
the jar receiving the off-water. Now it will be seen 
that as soon as the water reaches the level of the 
tube passing through the back of the tank, it will flow 
over into the outer tube communicating with the jar, 
and this tube, by acting as a syphon, will draw off all 
the water to the lower water level, vhich in my aqua- 


154 MARINE AQUARIA FOR ROOMS . 

rium is about 2 gallons. This is, of course, a great 
saving of trouble, as with only once attending to 
it, the water is made to rise to the highest level, and, 
instead of getting heated in the aquarium by re¬ 
maining there, it is drawn off into the darkness again. 
I think that with this arrangement it is almost im¬ 
possible that the water should get foul, except by the 
grossest neglect.” Whenever a film or scum is seen to 
settle on the surface of the water, it should be cleared 
off, either by laying sheets of blotting paper upon it, 
as you would remove dust, or by drawing off the 
surface water by means of a syphon. Such a film 
hinders the free passage of air to the water, and Mr. 
Lloyd has shown that water has a stronger affinity 
for the oxygen of the atmosphere it is in contact with 
than its nitrogen. 

The regulation of the light and temperature of 
marine tanks is quite as important a task as in the 
management of fresh-water aquaria, if not more so. 

Their temperature should always be low , so that 
the water feels cold to the hand. It should, however, 
never fall below forty degrees Fahrenheit. If the 
tank be so placed that it is difficult to prevent the 
heat unduly warming it, a small piece of ice may 
be placed in the water to replace that lost by eva¬ 
poration. Light is perhaps even more to be stu¬ 
died than temperature, as it stimulates the growth 
of the well-known green confervse which are such a 
source of trouble to the uninitiated. If the light and 


TEMPERATURE OF WATER. 


155 


temperature are both too powerful, we cannot expect 
other than the utmost disorder and zoological anarchy. 
Mr. W. R. Hughes, speaking on this point, says, “ It 
is certain that light is the primary question to be con¬ 
sidered in relation to aquaria. The presence of an 
uninterrupted volume, combined with a high rate of 
temperature, may in a few days convert an aquarium, 
which was in an efficient condition of health and 
beauty of the inhabitants, into a decomposing mass.” 
Moreover, so auxiliary is the effect of light or heat 
respectively, that it is necessary to reduce the light 
admitted to a tank when the temperature is rising. 
Fifty degrees, or from that to fifty-five is about 
the highest heat which should be allowed; and the 
light should be toned down as the water reaches the 
higher point. Mr. Lloyd insists with great emphasis 
upon the necessity of keeping the temperature low, 
and this, he contends, can only be effectively done by 
having a store of water several times the bulk of that 
in the show tank. 

It is evident that, do what we will, some of the sea 
water cannot fail to be evaporated during the process 
of fountain or syphon aeration ; or even when the 
surface only is exposed to the air. But it should be 
remembered that what is thus lost by evaporation is 
only the fresh part of the water. The salts are 
left behind—we cannot evaporate them ; and so they 
tend to render the remaining water all the salter and 
denser. Hence there is an immediate necessity for 


MARINE AQUARIA FOR ROOMS. 


156 

restoring the quantity of water lost, by adding a 
supply of fresh water. Distilled water is the best to 
replace the evaporated, as then we know no germs or 
other interfering agents are likely to be introduced. 

In constructing a marine aquarium there is no doubt 
whatever that pure sea water is the best. This can 
now be obtained through dealers, or the student may 
obtain it for himself, always taking proper precaution 
that the barrel or other means of conveying the salt 
water, contains nothing that would render it obnoxious. 
Always use the water as soon after getting it as 
possible, and do not allow it to remain in wooden 
vessels which may discolour it. When placed in 
the aquarium, add the Ulvce , Cladophora , or other 
useful, oxygen-yielding sea-weeds ; and let them grow 
before putting in any animals. When you think the 
water is fit, place in a few sea-anemones, adding 
them one at a time. It is much better to proceed 
slowly, than to be in a hurry, and have all the work 
to do over again. Mr. Gosse showed that it was 
possible to manufacture sea water, and gave the 
following formula for it: 

Common table salt .. .. ,. 3^ oz. avoir. 

Epsom salts. £ ,, 

Chloride of magnesium .. .. 200 grains 

Chloride of potassium. 40 ,, troy 

which should be added to a little less than 1 gallon 
of distilled water. This artificial “sea-salt” is now 





ARTIFICIAL SEA WATER. 


iS7 


specially prepared for aquarium keepers, and may be 
purchased at the natural history dealers. We confess, 
however, to a disinclination to its use, although we have 
seen some healthy and beautiful marine tanks, full of 
life and vigour, supported by water prepared in this 
manner. At Berlin and Hanover, the marine tanks 
have their sea water manufactured artificially. The 
best way to use it, after mixing carefully in an earthen 
jar, is to allow it to stand in a quiet place, with a few 
sea-weeds thrown into it, and afterwards expose it 
to the sunlight. Strangely enough, spores will then 
develop in it, having come from the atmosphere ; or 
been given off by the sea-weeds. Owing, however, to 
the conveniences which railways and railway excur¬ 
sions now afford, almost every intending aquarium 
keeper can get his own sea water from the sea itself. 

Sea water can easily be made to indicate the re¬ 
lative saltness or otherwise by using the “ specific 
gravity beads,” sold by London dealers. There are 
two kinds of them, both in the shape of pretty thin 
glass balls. One of these floats when the water is 
of the right strength, and the other sinks. Directly 
the floating ball begins to sink it indicates that the 
water is weak in saline matter ; whilst if the sinking 
bead rises, it is time to add a little fresh water until it 
falls again. Both these kinds of balls, or floats, are 
used in small tanks, and they are usually differently 
coloured, so as to be soon recognised. A good 


iS« 


MARINE AQUARIA FOR ROOMS . 


hydrometer, however, is much easier to use, and is 
altogether better. 

Fig. 114* 


A 



Self-acting Air-can for Aquatic Animals. 


Fig. 115. 



Undoubtedly one of the charms of marine aquaria 
consists in the personal collection of the objects. 






































SELF-ACTING AIR-CAN. 


159 


Most people have now their annual seaside “run,” 
and it is a poor place indeed if it have no rock- 
pools and no marine animals and plants there to be 
captured, stowed away, and brought home as sou¬ 
venirs of pleasant summer rambles. We have known 
a good many instances, however, in which the ani¬ 
mals thus collected have been lost ior want of a 
proper means of keeping them until they could be 
transferred to the tank ; and we therefore give the 
accompanying sketch of Mr. A. J. R. Sclater’s “self¬ 
acting air-can,” as one of the best contrivances we 
have hitherto seen for keeping aquatic objects, whether 
marine or fresh water. The following is the ex¬ 
planation of its structure: 

A is the cover of the can ; B the socket to fit the 
cover ; C the body of the can; D D plate with per¬ 
forated raised zinc, showing the water forcing itself 
into the chamber F, and then going back into the can 
again ; g the top of the cover, which rests on line h, 
sinking down one inch below upper rim, so that water 
forcing its way through the upper cover plate also 
goes back into the can again through the holes, as 
marked in cover on the under drawing i i ; j shows 
the hollow, and how it is fastened to the left side by 
a leathern strap k k passing over the head to right 
shoulder. It can thus be worn when riding or walking. 
L L is the cover of the can closed down into the 
socket; m in tin loops to pass the leathern strap 
through ; n 11 pillars to hold the under plate of cover ; 


160 MARINE AQUARIA FOR ROOMS. 

the plate not to go below o. Of course it is always 
best to transfer any captured aquatic objects to their 
new habitats as quickly as possible. Keeping them in 
unnatural conditions is cruel, and no true naturalist 
will inflict pain on the humblest creature if he can 
possibly avoid it. 


FIRST PUBLIC AQUARIA. 


l6l 


CHAPTER X. 

OUR PUBLIC AQUARIA. 

THE establishment of large public aquaria in English 
cities and towns is the best evidence we could desire 
of the progress of zoology. There can be little 
doubt that these important institutions will react 
favourably on scientific education by familiarising 
people with objects they were previously only ac¬ 
quainted with in books, and also by stimulating young 
minds to their further study. Their value to natural 
history cannot be overstated, for they afford means of 
observation which never existed before, both to study 
the habits and the embryological development of 
marine animals. 

To Mr. W. A. Lloyd belongs the merit of success¬ 
fully carrying out the idea of large public aquaria to 
their present issue. No other naturalist has enjoyed 
such a long and specialised experience in their con¬ 
struction and management, either at home or abroad. 
The continued success of the Crystal Palace Aquarium 
—which may be called the first public one of any 
magnitude, those at the London and Dublin Zoolo¬ 
gical Gardens and elsewhere being on a much smaller 
scale—undoubtedly encouraged the construction of 


M 


OUR PUBLIC AQUARIA. 


162 

aquaria at Brighton, Manchester, &c. A full and 
detailed description of that at the Crystal Palace will 
be found in the excellent ‘ Handbook ’ which Mr. 
Lloyd has written.* 

In large aquaria it would be utterly impossible 
to sufficiently aerate the water in the huge tanks by 
means of algse. The quantity required to be grown 
to oxygenate the water sufficient for a very few fish 
to be healthily kept would be so great that it would 
almost fill the tanks. Moreover, in these show tanks 
it is necessary there should be as little as possible to 
obstruct the observation for which they are con¬ 
structed. Even if sufficient aeration could be pro¬ 
duced by the presence of sea-weeds, that alone would 
not represent the actual marine conditions by which 
fish and other animals are naturally surrounded. 
The seething, restless condition of the ocean—with its 
huge volume of water moved by tides, currents, and 
storms, so that the waves raised by the latter are 
always entangling quantities of atmospheric air all 
over its broad surface — is best imitated in large 
aquaria by the circulation which is constantly hurrying 
masses of water from one place to another, and always 


* In 1861 Barnum had two white whales captured for him at the 
mouth of the St. Lawrence, and conveyed alive to his museum at New 
York, where they were exhibited in large tanks constructed for the 
purpose. Other tanks were shortly afterwards constructed by him, in 
which sharks, porpoises, “angel” fish, &c., were shown. These 
animals were kept alive by a stream of salt water from high tide. This 
was the first rude attempt at aquaria in America. 


AERATION OF AQUARIA. 163 

presenting new surfaces to the oxygenating influ¬ 
ences of the air. In fresh-water aquaria we need 
this mechanical aeration and circulation in the same 
degree, perhaps, although we there imitate the quiet 
condition of our still ponds and tarns. In our small 
parlour aquaria, constructed to maintain marine crea¬ 
tures, we also require its assistance, such as may be 
produced by the means already described ; but it 
should be remembered that here we are only imitating 
the natural conditions of rock-pools. On the other 
hand, in the huge tanks seen in every large public 
aquarium, it is sought to imitate the conditions of 
the open sea. 

A most important mechanical contrivance for 
aerating aquaria was invented by the late Mr. G. 
Hurwood, of Ipswich, in 1859. It consisted of an 
arrangement by which “the pressure of a stream of 
fresh water, such as exists in the pipes of waterworks 
in towns, or such as can be got from a high cistern 
already existing in a dwelling house, may be em¬ 
ployed to compress air, which compressed air in its 
turn forces a current of sea water into an aquarium.” 
This contrivance was first successfully adopted on 
a large scale at that erected in the garden of the 
Acclimatisation Society of Paris, in 1859, shortly 
after Mr. Hurwood invented it. It was afterwards 
partly applied by Mr. Lloyd to the Hamburg Aqua¬ 
rium, of which he then had the charge. The sea 
water in the Hamburg institution was “circulated 


M 2 


OUR PUBLIC AQUARIA . 


164 

partly by a water-pressure engine set in motion by 
the town waterworks, which drives a pair of water- 
pumps (instead of compressed air, as was done at 
Paris), and partly by a steam-engine which drives two 
other pumps.” 

Mr. Lloyd’s plan of keeping a large underground, 
dark reservoir for storage purposes, into which the 
water runs from the tanks after circulating through¬ 
out, and from which it starts again on its circulatory 
round, has been markedly successful. The water is 
bright and sparkling, and its temperature is thus 
always easily kept at from fifty to sixty degrees. The 
aggregate contents of the tanks at the Crystal Palace 
is only one-fifth of the contents of the reservoir. This 
readily enables the manager to at once empty any 
tank into it, should it get wrong, and the slight 
admixture of the turbid water would be unable to 
affect the good condition of the general volume. No 
animals are kept in the reservoir; the main aeration 
is produced by the mechanical agitation of circula¬ 
tion, and the constant injection of sprays of salt water 
entangling air into each tank. This is constantly 
going on, night and day, duplicate steam-engines and 
boilers being employed, in case of any accident occur¬ 
ring to one of them. The stoppage of this me¬ 
chanical circulation for some hours is attended by 
distressing symptoms, and Mr. Lloyd remarks that 
“the creatures in the tanks, and especially in the 
taller tanks, must be considered, to some extent, in 


CRYSTAL PALACE AQUARIUM. 165 

the light of persons in a diving-bell, whose existence 
depends on continuous pumping and injection of air.” 
The sea water issues from the pumps at the rate of 
from five to seven thousand gallons an hour, passing 
into the two largest tanks first. Thence it runs north 
and south, passing into and feeding all the rest. The 
sea water is unchanged , except about two per cent, of 
the whole, which is added to compensate for leakages, 
and one-half per cent, of fresh water, to supply the 
loss by evaporation. 

Mr. Lloyd’s method of employing large storage 
reservoirs has lately been attacked by Mr. Saville- 
Kent, in a paper read before the Society of Arts in 
March, 1876, chiefly on the ground of its great ex¬ 
pense, and also that so extensive a store of salt water 
is not required.* At the Brighton Aquarium the tanks 
are aerated by jets of air , injected into the water in 
its simple form; so that the mechanical arrangements 
are quite different from those at the Crystal Palace. 
Indeed, we may regard these two systems as being 
more or less on their trial before the world. Each 
has its merits, but that in practice at the Crystal 
Palace has been longer in existence, and has never 
shown signs of failure. At Brighton, moreover, the 

* Mr. Lloyd, in two contributions, one in the ‘Journal of the Society 
of Arts,’ for March 24, 1876, and one in the ‘ Popular Science Review/ 
for July 1, 1876, has sought to demonstrate by figures that the money 
capital of public aquaria cannot be more profitably spent than in large 
reservoirs of from five to even ten times the aggregate capacity of the 
show tanks. 


166 OUR PUBLIC AQUARIA. 

adjacency of the aquarium to the sea somewhat 
obviates the necessity for a large storage reservoir. 
The sea itself may be regarded as partly acting in 
that capacity, for all the salt water in the tanks is 
pumped directly from it into underground reservoirs, 
capable of holding half a million gallons of water. It 
takes about ten hours to fill these reservoirs. The 
circulation of the sea water in the tanks is carried out 
by means of compressed air, which is supplied to 
their lower parts. One supposed advantage in this 
method of directly injecting air into the bottom of 
each tank is that it will ascend through the entire 
volume of water, and will, moreover, first come into 
contact with any organic substances lying at the 
bottom, which require oxydisation. Another assigned 
reason for employing this system of aeration and 
circulation is its greater cheapness. This, however, 
Mr. Lloyd emphatically denies; even holding that it 
is eventually more expensive. We may expect, how¬ 
ever, that many of the public aquaria founded at 
seaside towns and resorts will be established on the 
Brighton pattern, owing to the advantages which 
contiguity to the sea confers, by enabling the manager 
to pump in the sea water direct, and as often as may 
be required. It has been found that the salt water 
near the shore is quite fit for aquarium use, especially 
if it be kept a time in the reservoirs, so that any 
mechanical sediments, &c., may subside. Another 
assumed advantage of the Brighton system of direct 


YARMOUTH AQUARIUM. I 6 y 

aeration by jets of atmospheric air is that it allows 
of each tank to be treated independently of the rest, 
if required. The Scarborough Aquarium is aerated 
on the same plan as that at Brighton. Mr. Lloyd’s 
method of injecting sprays of water which carry down 
fine air-bubbles to the bottom of the tanks, and then 
allows them to be distributed through the volume of 
water, however, has the support of all aquarium natu¬ 
ralists. Undoubtedly the expense of constructing 
storage reservoirs commensurate with the size of the 
largest public aquaria is very great, if carried out in 
the proportion of the method employed at the Crystal 
Palace; but if it be the means of preserving both 
sea water and animals in a continually healthy 
state, it cannot be deemed too great. Mr. Saville- 
Kent states that as the show tanks of the aquarium 
at Great Yarmouth are to hold 200,000 gallons of 
water, “ it would be necessary, in order to maintain 
the same ratio in the reservoirs as obtained at West¬ 
minster and the Crystal Palace, to construct reservoirs 
large enough to hold no less a qantity than 1,000,000 
gallons.” The Westminster Aquarium was con¬ 
structed under the direction of Mr. Lloyd, and, as 
already stated, it possesses show tanks of the capacity 
of 150,000 gallons. To keep up the healthy circu¬ 
lation of this water, after the manner described as 
being in practice at Sydenham, there is storage 
accommodation for 600,000 gallons, in underground 
reservoirs which resemble three railway tunnels placed 


OUR PUBLIC AQUARIA . 


168 

side by side, and which occupy the entire space 
underneath the grand promenade. 

The Manchester Aquarium is a good example of 
what can be effected in constructing and maintaining 
marine animals under purely artificial conditions. The 
smoky atmosphere of that town is proverbial, and 
perhaps the least said about directly aerating the 
tanks with it, as at Brighton, the better! From our 
experience, we should say it would be an additional 
element of acclimatisation for marine animals to enjoy 
Manchester air, seeing that even human beings get as 
far away from it as they can! This aquarium was 
for a long time under the direction of Mr. Saville- 
Kent, who states that it has been most successfully 
maintained with storage reservoirs constructed to 
hold a supply of water only equal to that contained 
in the show tanks. He further declares that, “ practi¬ 
cally it has been kept in the highest state of efficiency, 
with the water clear, and an abundant supply of fish 
of the largest size, with less than one-half of this full 
complement in the reservoirs.” The Yarmouth Aqua¬ 
rium was altered so as to adjust the storage reservoir 
to the show tanks after the plan which exists at 
Manchester. Mr. Kent contends that when sea water 
is sufficiently clear and aerated it is unnecessary to 
spend time and money in the formation of excessive 
storage places. Indeed, he goes so far as to observe 
that “it is an open question whether, by a trifling 
increase of the pumping power, and acceleration of 


SOUTHPORT AQUARIUM, 169 

the circulating stream, reservoirs might not be done 
away with altogether, substituting in their place a 
mere well or cistern, for the reception of the water 
flowing over from the tanks and feeding of the pumps.” 

The Southport Aquarium has rather a strange 
combination of the two methods of circulation and 
aeration which we have been discussing, viz. those at 
the Crystal Palace and at Brighton; one half being 
on one plan, and one half on the other. We under¬ 
stand, however, that recently the Brighton method 
has been given up, notwithstanding the adjacency of 
the Southport Aquarium to the sea; so that the 
whole management is now carried on after the Syden¬ 
ham fashion. The Southport institution has a large 
number of tanks; and here, as at the Crystal Palace 
and some other places, the commendatory plan of in¬ 
scribing the names of the objects on the sides of the 
tanks is carried out. It is absurd to compel everyone 
to purchase a guide book before he can understand 
what fish, &c., are before him ! The new arrivals of 
objects intended for public aquaria are usually placed 
in special and private tanks, until they are deemed 
sufficiently acclimatised to be transferred to the show 
tanks. 

In this state of captivity the animals, if healthy, 
soon feed heartily. For this purpose, at the Crystal 
Palace Aquarium and elsewhere, twenty-two special 
tanks are kept in which to preserve alive the crabs, 
shrimps, fish, &c., intended for food. The introduction 


170 


OUR PUBLIC AQUARIA. 


of this live food into the show tanks by the assistants 
is always an animated sight, the inhabitants soon 
learning the times and appearances of their keepers. 
In the Crystal Palace Aquarium, with only 20,000 
gallons of water in the tanks, the food supplied to the 
living objects costs 120/. per annum. 

We cannot do better than conclude with the follow¬ 
ing remarks by Mr. Saville-Kent, contained in his 
paper above mentioned as to his experience of the 
feeding habits, &c., of the marine animals he has 
superintended. Herrings, whether old or young, are 
partial to living food; feeding chiefly, in the latter 
instance, on entomostraca, and the larval young of 
the higher Crustacea. Such pabulum being difficult 
to obtain so far inland, a variety of substitutes were 
offered by way of experiment; but for a long time 
none successfully. Ultimately an irresistible bonne - 
bonche suggested itself, in the form of the hard part 
or adductor muscle of the common mussel. This 
substance, minced fine, being clean, hard, and white, 
with probably a somewhat crustacean flavour, was 
devoured with avidity by the little fish, and has 
constituted the chief staple of their existence ever 
since. In the course of a few weeks the whitebait 
became so accustomed to confinement as readily to 
take their prepared food from the keeper’s hand—a 
circumstance which would seem to indicate that young 
fish, like the young of other animals, are more readily 
susceptible of domestication, adult herrings not being 


NOCTURNAL FISHES . 


171 

known to display an equal amount of confidence to¬ 
wards those who tend them. The food question being 
settled, another difficulty presented itself, and this 
time one that threatened, sooner or later, to accom¬ 
plish the extermination of the whole shoal. Imme¬ 
diately succeeding their advent, a large number of 
these little fish were found dead each morning, at the 
bottom of their tanks, a circumstance which at first 
seemed inexplicable in association with their quiet 
behaviour during the day. A night inspection, how¬ 
ever, happily revealed the cause of their rapid destruc¬ 
tion. It was then seen that the nocturnal movements 
of the herring, at least in confinement, are altogether 
distinct from those seen by daylight. In the latter 
instance these movements are very quiet and uniform, 
the fish swimming round their tank in one shoal and 
in one continuous stream. At night, on the contrary, 
the shoal is entirely broken up, each fish taking an 
independent path, and darting from one side to the 
other with an amount of agility scarcely to be antici¬ 
pated by a mere daylight acquaintance with the 
species. It was during these active nocturnal move¬ 
ments that the fish struck against the rockwork of 
their tank and came to an untimely end. This mor¬ 
tality, however, was soon arrested by placing a dim 
light over their tank, which illuminated the outline 
of the rockwork just sufficiently to enable them to 
recognise and avoid it. With this dim light the fish 
still retained their active habits, and it was noticeable 


172 


OUR PUBLIC AQUARIA. 


that during these night hours they were more than 
ordinarily alert for food, dashing vigorously at any 
entomostracan or other minute organism that passed 
through the water. This circumstance would seem to 
explain why “ drift-net ” fishing for herrings can only 
be carried on successfully at night, that being the 
time when fish rise to the surface of the water to feed 
on the innumerable organisms which abound there. 
They are, in fact, so ardent at such times in pursuit 
of their food that they needlessly strike into the 
meshes of the net and get caught, just as the 
individuals under artificial conditions dash against 
the rockwork of their tank if sufficient light is not 
provided for their avoidance. This plan of dimly 
illuminating the whitebait tank was practised with 
equal benefit in association with other species that 
exhibited a tendency to injure themselves during the 
dark hours of the night, such species again being 
usually free rangers of the open sea. The picked dog¬ 
fish (Acanthias vulgaris ) is one of these, and is a 
variety so given to rendering itself an unsightly object 
by knocking its head against the boundaries of its 
tank, till it lays its cartilage bare, that it is frequently 
refused admittance in aquaria. Observations made 
at the Manchester aquarium, however, revealed that 
this self mutilation was invariably effected during the 
night; and a small light, enabling the fish to see and 
avoid the rocks, was found an effectual preventive 
remedy! 


PICKED DOG-FISH. 


173 


Fragments of mussels are usually given to such 
living marine objects, sea-anemones for instance, as 
are fixed. The eagerness with which their tentacles 
close upon them is very remarkable. A pair of wooden 


Fig. 116. 



Small-spotted Dog-fish (ScyIlium canicula). 


tongs, made after the fashion of sugar-tongs, only 
with very long arms, are employed to convey the 
food. But it is astonishing how little food sea- 
anemones, marine worms, and similar objects require, 
and we are perfectly convinced there is more danger 
from over-feeding them than in starving them. When 
we consider their almost vegetative habits it is evident 
there can be little loss of tissue from expenditure of 
muscular force. Expenditure of nervous force there 
cannot be, for these animals have no nervous systems, 
or developed in the feeblest degree. The water 
which continually bathes them contains invisible parts 

























*74 


OUR PUBLIC AQUARIA . 


of organic matter, as well as immense numbers of the 
zoospores of sea-weeds, and is, in fact, what Dr. Car¬ 
penter aptly terms it, in the “condition of a very 
weak broth.” Indeed, this “ weak broth ” is all the 
food the marine foraminifera, sponges, and many 
other lowly-organised animals have to feed upon. Sea- 
anemones, sea-worms, sea-squirts, sea-mats, &c., come 
in for a share of it, so that the quantity of solid food 
required to be artificially conveyed to manv of them 
is very small. 


AQUARIAN ANIMALS. 


175 


CHAPTER XI. 

MAMMALIA, REPTILIA, AND FISHES OF PUBLIC 

MARINE AQUARIA. 

The enormous size of the largest tanks belonging 
to our public aquaria, and the manner in which the 
mechanism of aeration and circulation of the water 
has been perfected, have rendered it possible to ex¬ 
hibit living -animals of all kinds whose lives are passed 
amid aquatic conditions. Hence, such /z/zz^-breathing 
animals as porpoises, grampuses, seals, sea-lions, alli¬ 
gators, crocodiles, and turtles, may be now maintained 
for a time, with almost as much ease as objects of a 
smaller size. The chief difficulty seems to be, not 
merely in maintaining these huge creatures in a healthy 
condition, but in capturing and transferring them un¬ 
injured to the tanks. As has already been stated, it 
is usual to keep the captured animals in places ap¬ 
pointed for the purpose, until they are more or less 
acclimatised, before they are turned out for public 
exhibition. This transitional stage seems to be neces¬ 
sary in the cases of most animals. Within the next 
few years our public aquaria will be enriched with 
many other species of huge fresh-water and marine 
animals, for one of the tanks at Brighton is almost 


176 


MAMMALIA , REPTILIA , £7T. 


capacious enough to admit of the evolutions of a 
whale.* A rare species of grampus (Grampus griseus) 
was placed there in 1875, but unfortunately it only 
lived a day. Porpoises are much commoner, and if 
there are two or three placed together, they appear to 
live under these artificial conditions for a longer time. 
Two of these animals lived for five and seven months 
respectively, in the Brighton Aquarium, and became 
so tame that they would take their food from the 
hand of one of the attendants, and came like dogs 
from the farther end of their tank at the sound of his 
whistle. The habits of animals undoubtedly must 
have a great influence on the ease or difficulty with 
which they are kept. Some are solitary, others 
gregarious, or social. The latter pine or are restless 
when alone, but become more cheerful when provided 
with companions. Such is the case with the porpoise. 
Fish of the herring tribe are its usual food. The seal 
is another animal easily tamed, and for years indi¬ 
viduals have been conveyed about the country and 
exhibited at fairs, &c. It will be remembered that 
one species acquired a good deal of notoriety from 
its being exhibited in London as the “ Talking Fish.” 
Several specimens have been and still are kept at the 
Brighton, Southport, and other aquaria. At Brighton, 
however, the chief living objects of interest are the 

* Owing to the depressed, or horizontally flattened tails of marine 
mammals (for the purpose of diving), the tanks are required to be 
exceedingly deep if these animals are to be kept healthy. 


SEALS. 177 

nuge “ sea-lions,” or eared seals ( Otaria ), from the 
South Pacific. 

The reptilia are not difficult to keep under the 
artificial conditions of aquarian life, owing to their 
more sluggish habits. Alligators and crocodiles 
prefer dark retreats. At Southport, Manchester and 
Brighton, several species of alligators are exhibited 
in water cages provided for the purpose. They are 
fed with a pair of forceps, and take their food without 
any demurrance to the artificial conditions under 
which it is offered to them. A living gigantic edible 
turtle—one of the few marine reptiles surviving out 
of the host of extinct forms which swarmed the seas 
in the oolitic period—was presented by Her Majesty 
the Queen to the Brighton Aquarium in 1875, and, 
we believe, is still kept there. It weighs no less than 
3 cwt., and will be easily recognised by the familiar 
plastron or shield on which many spectators have often 
seen chalked the words, “For soup to-day!” in the 
London streets. Another species of turtle is that 
called the “hawk’s-bill ” (Chelonia imbricata). Although 
in reality a native of the more southerly parts of the 
Atlantic, this species is occasionally found straying 
into British waters. It is much smaller than the edible 
turtle, with the plates of its shield overlapping, hence its 
specific name. It is these plates that, when polished, go 
by the name of “ tortoise-shell.” As regards its diet, 
it is almost omnivorous, as its strong hawk-like beak 
indicates, when compared with the weaker mandibles 

N 


178 MAMMALIA , REFT I LI A, ETC . 

of the sea-weed-loving turtles. It is a pretty, active 
little animal, readily acclimatised, and therefore a 
great favourite in public aquaria. 


Fig. 117. 



Hawk’s-bill Turtle (Chelonia imbricata). 


Mr. Lloyd’s restriction of aquaria to animals that 
possess gills and not lungs is not altogether re¬ 
cognised by nature, unless he refers solely to their 
mode of breathing, to which, of course, all the 
mechanical aeration of the water is adapted. Reptiles 
and mammals are frequently inhabitants of the 
same seas as the fishes; and there is no reason why 
we should not acknowledge this fact. But, un¬ 
doubtedly, fishes are more pleasing and familiar 
objects in the water than anything else, and as they 
are distributed everywhere with an abundance that is 
unfailing in its supply, they will always continue to 
be among the chief attractions of a marine aquaria. 
Few of them are adapted to live in shallow or tidal 




TURTLES. 


17 9 


tanks, which are therefore usually restricted to zoo¬ 
phytes, certain crustaceans, &c. The fishes which 
seem to live in shallow water most readily are 
the ballan and other wrasses, the rock goby, the 
fifteen-spined stickleback, and several others. One 
reason why fish will always be favourite objects 
is the marvellous variety in their sizes, shapes, and 
habits, in addition to their more intrinsic importance 
as food. Many people never see anything but dried 
fish, or stale fish exposed on stalls ; and these are as 
different from the graceful objects seen moving about 
in capacious tanks as the stuffed and labelled birds of 
a museum are from the winged and animate choristers 
of the woods! 

The thin, worm-like lancelet (A mphioxus lanceolatus ) 
is kept alive at Sydenham, six of them coming from 
Naples alive, in a post-letter! This little fish is not 
more than a couple of inches in length, and is a 
native of the Mediterranean. So singular is its inter¬ 
nal structure (possessing neither brain nor vertebrae), 
that an order had to be prepared by naturalists for its 
separate reception. To zoologists it represents the 
embryonic condition of fishes and mammals, in per¬ 
manently possessing a notochord. The mud-fish (Pro- 
topterus annectens) is shown at Brighton, and this object 
is even more scientifically interesting than the lancelet, 
as being a veritable “ missing link ” between reptiles 
and fishes. It belongs to an ancient class, of which 
the most remarkable living forms are now to be found 

N 2 


I So MAMMALIA , REPTILIA, ETC. 

in some of the Australian rivers. In the early liassic 
period these Australian fishes lived in British estuaries, 
as is proved by the occurrence of their teeth in the 
Rhsetic beds of Gloucestershire and elsewhere. The 
Brighton mud-fish is nearly related to them, although 
a native of African streams. It possesses both rudi¬ 
mentary lungs and gills, whilst its elementary limbs 
can hardly be distinguished as legs or fins. 

The most interesting of aquarium fishes, however, 
are undoubtedly those belonging to the shark family. 
Few of them are eaten as food, but many of them are 
more or less familiar to the reading public. No fishes 
have more graceful motions in the water, on account 
of the ease with which their unequally lobed tails 
enable them to turn over and round about. They are 
very active, especially at night, when they are liable to 
hurt themselves against the rockwork, unless some 
such ingenious arrangement of dimly lighting the 
water be adopted as we have already quoted from Mr. 
Saville-Kent. The most familiar of the fishes of this 
class which are kept at Brighton, the Crystal Palace, 
and elsewhere are the smooth hound, or skate-toothed, 
shark (Mustulus vulgaris). The tope (Galeus canis ), 
also called the “ miller’s dog,” has been so far tamed 
as to bring forth “litters” at Brighton, and the 
young (as is usual in some fishes of this class) were 
brought forth alive and not as eggs. The largest 
individuals of this fish, which is nearly as rapacious, 
although not so abundant, as the common dog-fish— 


DOG-FISHES. 


181 

often measure six feet in length. The common dog¬ 
fish (A canthias vulgaris) is exceedingly abundant, as 
every fisherman is aware, and is so easily kept in 
aquaria that it may be seen in all the public ones. 

Fig. 118 . 



Common Dog-fish (Acanihias vulgaris). 


Few other fish have such an extensive geographical 
distribution as this. Fishermen dread it on account 
of the sharp spines which are placed before the two 
dorsal, and also behind the ventral fins, for these con¬ 
stitute dreadful weapons of attack or defence. No 
other species of fish plays such havoc on herring 
shoals as this, for it mangles what it cannot eat or even 
kill, and seems to delight in bloodshed and carnage. 



























182 


MAMMALIA , REPTILIA, ETC. 


Only those acquainted with this fact can understand 
the bitter hatred which fishermen in general entertain 
for the dog-fish. When they catch it they will often put 
it to all kinds of torture, as if in revenge ; and the fish 
almost seems to know that it has to run the gauntlet 
of its enemies, and therefore shows no mercy in re¬ 
turn, if it can only obtain the chance to injure its foes. 
It is very abundant off our shores, but we have not 
heard of its being eaten, except off some parts of 
the Lancashire coast, and we very much suspect that 
this is done more from motives of revenge than 
gustatory enjoyment! The small-spotted dog-fish 
(ScyIlium canicula ) is rarer, and of a more graceful 
shape, so that it is a “ stock ” object in marine aquaria. 
Many of these fishes, as well as the skates, have a 
peculiar way of forming egg-cases, and these are very 
interesting to the zoologist, because in some instances 
they are so transparent that he can witness the entire 
development of the contents through them. These 
egg-cases may always be picked up on the beach, 
especially those of the skates, which, on account of 
their shorter tendrils, seem to be more easily detached 
from the objects to which the fish originally fastened 
them. These egg-cases are, however, usually found 
empty. They go by the popular name of “pixy 
purses.” We give figures of those of the common 
skate (Batis vulgaris ), and of the smaller spotted dog¬ 
fish {ScyIlium canicula). The latter has very long, 
pea-like, but hollow tendrils, which wind round the 


EGGS OF SKATE, ETC . 


183 


stems of sea-weeds, stones, &c., the parent fish de¬ 
voting much time and pains to properly fastening 
them. The sea water gains admittance to the embryo 



Fig. 113. 


Pixy Purses. 


down these hollow tubes. The larger spotted dog-fish 
or ‘‘nurse hound’' (ScyIlium stellare) are other good 
objects for a large marine aquarium. Like the small 











184 


MAMMALIA , REP LILIA f ETC. 


spotted, they are natives of deep water, and therefore 
require a deep tank. Perhaps this is on account of 
their nocturnal habits, as they hide away from the 
light in the deep parts where it cannot penetrate, 
and are all more or less surface swimmers by night. 
In aquaria they are fond of taking shelter in such 
nooks and crannies as the rockwork may have pro¬ 
vided for them. Sometimes they are seen lazily 
reclining on the shingly bottom, with their bird-like 
eye-membranes closed, but the practical announcement 
of “meal time” is sufficient to rouse them into a state of 
activity only excelled by a batch of hungry carnivorous 
animals in a menagerie, to whose lithe and supple 
motions, those of the “ground sharks” or dog-fishes 
might be compared. 

The fact that the latter fishes bring forth their 
young in egg-cases, and not alive, as the sharks do, 
and the resemblance of these egg-cases to those of the 
rays, shows us that the two groups are nearly related. 
Perhaps one of the “ connecting links ” is the angel, 
or monk fish (Rhina squatina) ; although why the 
popular name should be so easily convertible is not 
apparent. There is undoubtedly a strong resemblance 
between the rounded head and broad-spread pectoral 
fins of this fish and the hooded cowl of a monk. This 
fish is tolerably common in the Irish Sea, where it is 
shunned by the fishermen on account of its habit of 
simulating death, and snapping at them when least 
expected. Like many others of its class it is noctur- 


THORNBACKS. 




Fig. 120. 


nal in its habits, feeding on small flat-fish, Crustacea, 
whelks, &c., indeed almost anything it can obtain. It 
usually lies half-buried in the sand, which it strews 
over its body by means of its tail. The females, how¬ 
ever, bring forth their young alive ; so far, therefore, 
the connecting link be¬ 
tween the dog-fish and 
rays is destroyed. The 
shape of these fishes, 
nevertheless, is a good 
indication of their af¬ 
finities to the skates or 
rays. At the Brighton 
Aquarium the angel 
fishes have always done 
remarkably well. The 
thornback or skate (. Raia 
clavata) is one of the 
best known of our flat¬ 
fishes, and is much eaten 
by the poorer classes of 
this country. Those 
who have partaken of 
the flesh of the wings , 
or broad pectoral fins, will, however, be inclined 
to say that it is “a dish for a king.” The thorn- 
back is easily acclimatised, and will live in the same 
tank with cod, dog-fish, sturgeon, &c. The homelyn 
or spotted ray (Raia metadata ) is also eaten as food. 


Thornback (Raia clavata). 



186 MAMMALIA , REPTILIA , £TC. 

This is usually a smaller, but much more graceful 
fish than the former. In it the spines are not dis¬ 
tributed over the body, but are confined to a single 


Fig. 121, 



The White Ray (Ram lintoa). 


series running down the back and tail. The common 
skate (Raid batis) is a different species from either, 
and its flesh is usually preferred to theirs. On the 
eastern coasts some very large individuals occur, and 









































































































CAT-FISH . 187 

indeed it is the stock fish of that district The 
Brighton Aquarium contains all the foregoing species, 
as well as the white or sharp-nosed ray (Ram lintoa). 

The cat-fish (Annarhicas lupus) is another singular 
species about which fishermen have “ spun yarns” for 
untold years. It is sometimes called the “ wolf-fish,” 


Fig. 122. 



Cat-fish (Annarhicas lupus). 


and this is acknowledged in its specific name. Its 
savage appearance, caused by the fierce display of 
naked teeth, do not belie its habits; for when it 
is caught it will snap at and seize any object the 
fishermen may present to it. In addition to these 
teeth the cat-fish also possesses roundish palatal 
teeth, set close together like a miniature pavement of 















188 


MAMMALIA , REPTILIA , ETC. 


boulder stones. These are for the purpose of crushing 
the shells of the crabs and other crustaceans on which 
it most delights to feed. It belongs to the usually 
harmless family of the blennies, one of which, the little 

smooth blenny (Blennius 
pkolis), derives its name 
from a Greek word sig¬ 
nifying “slime/’ on ac¬ 
count of the abundant 
mucus which, in common 
with all fishes, it secretes from the medial line of scales, 
which are perforated to allow the mucus to exude, and 
thus decrease the friction caused by rapid movements 
in the water. Many larger fishes support parasites on 
their scales, and these are usually crustaceans which 
have undergone a very strange degradation. Of course, 
they are popularly spoken of as “ fish-lice/’ and have 
been regarded as unhealthy signs on the part of the 
fish. Any fishmonger, however, will tell you that the 
fish thus affected are usually stronger and better than 
those without them, and Van Beneden has shown that 
the parasites really live on the excessive mucus, which 
they thus check and prevent decomposing; so that 
they are actually serviceable to fishes. The smooth 
blenny is a good shallow tank object, and may be 
kept and even tamed there easily, especially if the 
tank represents the hiding-places of the rock-pools 
in which it delights when free. The male, like the 
stickleback, will defend the eggs against enemies. 


Fig. 123. 



The Blenny (Blennius pholis). 


BLENNIES. 


189 


Some of the blennies are really very attractive objects, 
especially the species called the “butterfly blenny ,, 
(Blennius ocellatus ), which is kept at the Crystal 
Palace, Brighton, &c. Its dorsal fin is largely de- 


Fig. 124, 



Butterfly Blenny (Blennius ocellatus). 


veloped, and is seen to great advantage when the fish 
is swimming about, the dark blue or brown spots with 
which it is adorned giving it something of a butterfly 
appearance. It is not by any means so common 
in our seas as the viviparous blenny (Zoarces viviparus ), 
a fish which goes by the name of the “green-bone” 
along the eastern coasts, where it is very common, on 
account of the deep-green colour of the bones when 
the fish is cooked. This species departs from the 
usual habit of fishes in bringing forth its young alive, 
the reason being that the ova are kept longer in the 
body of the female. The young are very pretty 
objects, especially under the microscope, where the 
circulation of the blood is plainly visible. Small 



190 MAMMALIA , REPTfLIA, ETC. 

though they are, they seek their own food as soon as 
they are born. Some of the blennies can wriggle out 
of the water by means of the free rays of the ventral 
fins; and the smooth blenny is especially fond of 
climbing on the rockwork of the tanks just above the 
water level. So tamable is this species that Mr. 
Lloyd says it will even feed when taken into the 
hand. 

The gobies are a useful and interesting series of 
aquarium objects, on account of the ease with which 

they can be kept in a 
state of healthy activity. 
The largest species is 
the black or rock goby 
(Gobius niger\ which 
may be seen in every 
public aquarium in a 
very tamed condition. 
It has a kind of “ suck¬ 
ing fin ” on the ventral 
or under surface, by 
means of which it can 
attach itself to the 
smooth face of the glass, 
on which it sometimes 
deposits vast quantities 
of minute eggs, and then watches them most pertina¬ 
ciously. It abounds in our rock-pools, and may be 
easily captured there by means of a hand-net. 


Fig. 125. 



Ventral surface of the Rock Goby 
(Gobius niger), showing sucking fin. 
















WHITEBAIT . 


191 

Another species, the spotted goby ( G . minutus) is 
much smaller in size, and very closely resembles the 
sandy bottom in which it hides, so that it often 
requires a keen eye to detect it when hiding up. 
Among fishermen this species goes by the name of 
“ polewig,” or “ pollybait,” and as it abounds in the 
lower part of the Thames, it goes largely to make up 
the somewhat heterogeneous piscine compound known 
as “ whitebait ” l 


192 


FISHES FOR MARINE AQUARIA . 


CHAPTER XII. 

FISHES FOR MARINE AQUARIA. 

The most attractive marine fishes kept in our public 
aquaria are unquestionably the wrasses, gurnards, and 
dragonets. Many of them are resplendent with the 
most beautiful colours and tints, which rival the hues 
of tropical birds and insects ; and as they all bear 
confinement well and are not difficult to procure, we 
cannot be surprised at their being aquarium favourites. 


Fig. 126. 



Ballan Wrasse (Labrus maculatus ). 


The wrasses are crustacean and shell-fish feeders, as a 
rule, and their teeth are peculiarly adapted for picking 
shells off rocks. The ballan wrasse (Labrus maculatus) 
usually assumes mingled colours of blue and green ; 
occasionally it will be adorned with russet-brown, 
orange, and yellow. It is this chameleon-like power 



THE WRASSES. 


193 


of assuming fresh colours that has undoubtedly multi¬ 
plied the species beyond requirement, and hence we 
find more synonyms among the wrasses than in any 
other group of fishes. In addition to the prominent 
rows of front teeth, the wrasses have the power of 
elongating the jaws, and also possess protrusile lips, 
whence their generic name of “ labrum,” a lip. These 
peculiarities as well as their tints have caused them 
to be termed “ sea-parrots’’ among fishermen—another 
name they bear is that of the “ old wife.” The ballan 
wrasse is the commonest species, and attains the 
largest size, often weighing three or four pounds. 
Frank Buckland tells us, in his charming work ‘ Popular 
History of British Fishes,’ that this species on the 
north coast of France is usually red, and there goes 
by the name of the “ red old woman.” The adjective 
name of colour changes with that of the fish to green 
and yellow, but the “old woman” remains. From 
what Mr. Couch says, these fish appear to have habits 
not unlike those of the common stickleback, the 
largest individuals being lords of their respective 
districts. The red wrasse (Labrns mixtus) female, is 
distinguished by the three dark and four light rose- 
coloured spots which appear at the base of the hinder 
part of the back fin. These vary in number, so that 
this species is also called the “ double spotted,” when 
there are but two dark spots. The rest of the body 
is usually a fine red on the upper, and a pale orange 
on the lower part of the body. Mr. Kent tells us that 

O 


194 FISHES FOR MARINE AQUARIA. 

the best food for the aquarium wrasses is the common 
shore crab (Caremus meznas ), the ballan wrasse being 
so fond of it that specimens dropped into their tank 


Fig. 127. 



Blue and Red Cuckoo Wrasse (Labrus mixtus), male and female. 


are torn into pieces before reaching the bottom ; but 
Mr. Lloyd states that shrimps are their most favourite 
food. The colours and markings of the male and 
female wrasses generally differ from each other, and it 





























































































RED AND BLUE WRASSES. 


*95 


has been found from aquarium experience that of the 
two species named the “red” and “blue,” the former is 
th q young fish.* This colour is also that of the female, 
so that the fact of highly-adorned male fishes as¬ 
suming the tint and colour of the female when young, 
is analogous to the rule which prevails among many 
birds, of the young male bearing the plumage of the 
adult female. The cuckoo wrasse (Labrns mixtus') is 
to be seen in public aquaria, the males and females 
in the same tank, being both highly coloured, but 
so different in tint and marking that until recently 
they were regarded as different species. 

The corkwing and rainbow wrasses are distin¬ 
guished from those just named by the edge of the 
gill-cover being finely toothed or crenated, hence 


Fig. 128. 



Corkwing Wrasse (Crenilabrus Norwegicus). 


their generic name of Crenilabrus. The true wrasses 
are thus marked when young, but lose the teeth 
as they reach their adult condition. The corkwing 
(C. Norwegicus ) is not a very common British fish, 

* Labrus variegatus and Labrus trimaculatus are the male and female 
of one species, Labrus mixtus. The green wrasse (Z. lineatus ) is the 
young of Z. maculatus. 


O 2 



196 FISHES FOR MARINE AQUARIA. 

smaller than the species just mentioned, but not less 
beautiful in its yellowish green body, variegated with 
bars of a darker colour. Its fins are usually of a 
brown colour, and there is a characteristic dark spot 
at the base of the tail. The rainbow wrasse (Fig 129) 
is a rare fish, whose name is borrowed from its 
prismatic tints. As the specific name implies, it is 
very abundant in the Mediterranean. 


Fig. 129. 



Rainbow Wrasse (Julis Alediterranea). 


The dragonet, or yellow skulpin (Callionymus lyra) 
is another common aquarium fish, whose gorgeous 
colours and dragon-like fins and appearance are suffi¬ 
cient recommendation for its introduction. It is not 
a common British fish ; but this may be because it is 
fond of deep water, and of keeping at the bottom. 
Like the wrasses, the male and female are differently 
coloured, and were formerly believed to be different 
species. The male is easily distinguished by the 
very long dorsal fin ray. Their green eyes gleam 
with a beautiful fire-like expression, and are pro- 



DRAGONETS. 


*97 


minently fixed on the head. The head is usually 
striped with blue, on a yellow ground. The dusky 
dragonet is the female, and was formerly called 
Callionymus dracunculus . It is a much commoner, 
and less beautiful, British fish, having, as its popular 


Fig. 130. 



Yellow Skulpin, or Gemmeous Dragonet (Callionymus lyra ), male. 

name imports, a dingy hue. The long dorsal fin is 
absent in the female. Its colour is usually a reddish- 
brown, and therefore it goes by the name of the 
“ fox.” 

The “angler fish” ( Lophiuspiscatorius) is a creature 
possessing such a singular structure and habits that 
we cannot wonder it is a favourite object in our public 
aquaria. Sailors and fishermen are never at a loss in 
drawing comparisons, and every animal which has 
attracted their attention usually rejoices in several 
names. This is the case with the angler fish, also 
called “ toad fish,” “ sea-devil,” and “ fishing frog.” 
In shape it is not unlike a huge tadpole, and one of 







I 9 § FISHES FOR MARINE AQUARIA. 

its peculiar organs illustrates to us the ease with 
which nature sometimes modifies, transforms, and 
specially adapts one part of the animal frame to an 
extraordinary use. The back or dorsal fin in fishes 


Fig. 131. 



Angler Fish (Lophius piscatorius). 


is usually supported by fin rays. Not unfrequently 
one or more of these is larger than usual (as in the 
dragonet and weever), and then becomes a weapon of 
offence or defence. But in the angler fish, the first 
three spines are modified into long tentacles , and 
removed from the back tc the head (see Fig. 131). 








































































ANGLER FISH. 


199 


Bending gracefully over in front of the mouth, the 
animal now employs these modified spines as artificial 
baits. The fish is concealed in the mud, but gently 
waves these organs about as if they were moving sea- 
worms, in order to attract smaller fishes on the look¬ 
out for food. The front ray is slightly clubbed at 
the end, and adds to the tempting look of the living 
bait. The mouth of the angler fish is extraordi¬ 
narily large, and is armed with a row of teeth that 
would certainly deter even the most foolish of little 
fishes, and in spite of the most attractive of baits, if 
they beheld it. As we have seen, however, owing to 
its habit of burying in the sand or hiding among the 
rocks, the head is concealed. Mollusca as well as 
Crustacea are equally fair food to the angler fish, 
whose palate is set all over with pavement-like teeth, 
for the purpose of crushing the shells and carapaces. 

The lump fish, or “ lump sucker” as it is also called 
(Cyclop terns lumpus ), is further known by the names 
“ sea-owl,” “ cock-paddle,” “ sea-hen,” &c. It is a 
very abundant fish on the southern and eastern 
coasts, and its bright colours and unfish-like form 
make it a favourite object in the aquarium. Few 
people would recognise it as a British fish when alive, 
for, although we have frequently seen it exposed on 
fishmongers’ stalls, the colours soon fade after death, 
and the semi-translucent look it has when alive in the 
aquarium is utterly gone. Its popular name is de¬ 
rived from the saucer-shaped disk, which may be seen 


200 FISHES FOR MARINE AQUARIA. 

between the two pectoral fins. This is a sucking 
disk, and by its means the Cycloptevus can bring itself 
to an anchor in a strong current, where perhaps it 


Fig. 132. 



Lump Sucker (Cycloptevus lurnpus). 


might fall a victim from its own weak swimming 
powers. Its other name of “ sea-hen ” is also well 
deserved, for its young—which are most lovely little 
creatures—sportively follow the mother-fish about as 






















LUMP SUCKER. 


201 


if they were chickens. Their frolicsome ways make 
the young exceedingly interesting and amusing 
objects. The male fish is believed to “ mount guard” 
over the eggs, after the fashion set by the little 
stickleback. Some of the lump fish often weigh ten 
or twelve pounds when full grown. 

Speaking of the stickleback reminds us of a 
common species, generally known as the “fifteen- 
spined stickleback” (Gasterosteiisspinachia), the largest 


Fig. 133. 



Fifteen-spined Stickleback {Gasierosteus spinachia). 


of its kind. This pretty fish is never more than six 
inches in length, but its body is exceedingly long in 
comparison with its breadth, so that it can dart 
through the water with the rapidity of an arrow. 
Like its fresh-water relative, this fish constructs, and 
even stitches and glues together, a nest, usually of 
sea-weed, and the male defends the eggs laid there so 
determinedly that he appears to be an animated 
arrow, constructed for the special purpose of “charging” 
other and huger fishes desirous of making a meal of 
the nutritious ova. Its spines are capable of inflicting 









202 


FISHES FOR MARINE AQUARIA . 


a severe wound, both on fish and man, whence its 
name among the west-country people of “ sea-adder.” 
It is the two rows of elongated hard plates under¬ 
neath the bodies of sticklebacks which have given 
them the name of Gasterosteus , i. e. “ bony-belly.” 
The fifteen-spined species is a shore-loving fish, and 
should therefore be kept in a shallow or tidal tank. 
The “ pogge,” or armed bull-head (Aspidophonis Euro¬ 
peans) is not distinctly related to it, but its body is 


Fig. 134 - 



Armed Bull-head, or Pogge (Aspidophorus Europceus), 


more octagonal, being covered with eight rows of 
strong plates. The mouth is furnished with curious 
cilia. This fish is a very graceful species, but terribly 
destructive to the young shrimps, prawns, and lobsters. 
In pursuit of the latter species they frequent the deeper 
parts of the sea, and in the aquarium may be seen 
keeping close to the floor, whose tint so well comports 
with that of their bodies that it screens them from 
observation. Indeed, to a certain extent the pogge 






THE GURNARDS. 


203 


has the chameleon-like power of changing its tints 
according to the ground it haunts. Few fishes are 
therefore better defended against enemies, if we take 
into account the mail-clad body and the deft means 
of concealment they have by simulating the colour or 
tint of their hiding place. 

In many respects the gurnards are aquarium 
favourites. The elegant shapes and usually bright 
colours and tints of our British species would be 
quite sufficient to induce the naturalist to place them 
in his “ show tanks.” Those who have seen the 
larger sapphirine gurnard alive will not soon forget 
the exceedingly bright colours on the very large 
pectoral fins, which have earned for it its popular 
name. Some of the species are called “ Butterfly 
Gurnards ” from their coloured spots, streaks, and 
tints. Their thin and tapering bodies contrast strongly 
with their large and somewhat angular heads. All 
of them have well-developed pectoral fins, and it is 
these, when coloured, that cause them to have 
something of a butterfly appearance whilst swimming. 
We have seen how in the angler fish three of the 
dorsal fin rays are modified both as to their use 
and position, so that they serve as natural angling 
baits by which the fish attracts its prey. In the 
gurnards we have a modification of the first three 
of the rays of the pectoral fins, which are actually 
used as legs, the gurnards being able to creep along 
the sea-floor for some distance by their aid. Their 


204 


FISHES FOR MARINE AQUARIA. 


mode of walking very much resembles that of the 
lobster upon its slender jointed feet. These impro¬ 
vised feet also disturb many kinds of animals hiding 
under the sand, which soon fall a ready prey. The 
streaked gurnard (Trigla lineatd) possesses exceed¬ 
ingly rich tints, especially when young, insomuch 


Fig. 135. 



that in the water it suggests the appearance of some 
gaily-coloured tropical bird. Its usual adult length 
is about 12 inches. The head, mouth, back, dorsal 
fin, and tail are of a vermilion colour ; and sometimes 
of a dusky red. Its eyes are of a most lovely and 
brilliant blue. The dorsal fin is marked with bars of 
red and pinky clouds. The medial line is sometimes 
a deeper red, whilst the large red pectoral fins are 
further adorned with spots and markings of gre&n and 
blue. The spots are most numerous in the older fish, 
and fewer and larger in the younger. The grey 
gurnard (Trigla gurnardas ) is a very common fish, 





GREY GURNARD 


205 


occurring on our coasts in extensive shoals, which are 
much sought after by fishermen, on account of the 
demand for this kind of food among the lower classes. 


Fig. 136. 



Grey Gurnard (Trig la giirnardus). 


Its pectoral fins are not so large as those of the 
streaked gurnard, and its colours are less brilliant and 
striking. The piper (Trigla lyra) has a comparatively 
larger head than the preceding species, whilst its body 



































































20 6 


FISHES FOR MARINE AQUARIA. 


is more slender and tapering. It is very abundant 
on the southern and western coasts of England. 

A fish which bears a bad reputation among the 
fishermen is the lesser weever, or “ sting fish ” 
(Trachinus viperd). It is said to lie on the bottom of 


Fig. 137. 



Piper ( Trigla lyra). 


Fig. 138 . 



Lesser Weever (Trachinus viper a). 


the boat quiet enough until something or somebody 
comes within its reach, and then to bound up and 
drive the sharp thorn-like rays of its dorsal fin into 
its enemy. Dr. Gunther has proved that the fisher¬ 
men are right in holding that the wound thus made 
in the flesh is poisoned, and that the double-grooved 




THE BASSE. 


20 7 


dorsal spines are poison organs, the poison being con¬ 
tained in cavities of the spines until poured out.* It is 
not a very beautiful fish, its head being snakish-looking 
and ugly. The body is adorned with slanting green¬ 
ish-yellow bars, and is seldom more than 6 inches in 
length ; so that it is not to be confounded with another 
species, the greater weever (Trachinus draco ), some¬ 
times called the “ dragon fish.” The latter bears sharp 
strong spines on the upper part of its gill-covers, but 
they have not been scientifically discovered to be 
poisonous, although popular belief declares they are. 
Bathers are not unfrequently wounded by this fish’s 
spines. The former species only is usually kept in 
aquaria, but at the Crystal Palace the draco is also 
exhibited. Both species are fond of burrowing in the 
sandy floor of the tank. 

The basse (Labrax lupus) is a sea - perch, and 
usually thrives well in aquaria. Its body is very 
symmetrically shaped, and it seems to take pleasure 
in keeping its large silvery scales clean by rubbing 
itself among the sand and shingle. It is sometimes 
sold as “ white salmon,” for it much resembles that 
fish in shape and colour, but it is not spotted. The 
scales, also, are much larger, and the flesh is white , 
and in taste resembles that of the turbot. The 
Romans seem to have been much fonder of this fish 
than we are, and there can be no doubt whatever as 

* Mr. Lloyd’s experience of this fish, in aquaria, does not bear out the 
character given to it by our fishermen. 


208 


FISHES FOR MARINE AQUARIA. 


to their superior judgment concerning it as a food- 
fish. The specific name of lupus (a wolf) was given 
to the basse on account of its hunting its crustacean 
food in packs. It is a good fish for summer sea¬ 
angling, either from open boats or the ends of long 
piers. 


MIGRA TORY FISHES. 


209 


CHAPTER XIII. 

FISHES FOR MARINE AQUARIA. 

The so-called “migratory” fishes, as the mackerel, 
herring, pilchard, sprat, &c., are more difficult to keep 
long in active health in our marine aquaria than those 
which prefer to pass their lives always in the same 
locality. All of them are gracefully-shaped fish, and 
the mackerel, in addition, is one of the most beauti¬ 
fully marked and coloured. Their well-known value 
as food-fishes, and the fact that everybody is familial 
with their appearance, was a strong inducement for 
the managers of the first-formed aquaria to exhibit 
them in their show tanks. All of them are more 
active by night than by day, and we have seen how 
Mr. Henry Lee and Mr. Saville-Kent ingeniously 
prevented the young herrings from mutilating them¬ 
selves. When mackerel were first introduced into 
the Brighton Aquarium in 1872, some of them beat 
themselves to death by dashing against the rockwork. 
Since then they have been acclimatised, and living 
specimens may now be seen there which have lived 
ever since, and grown considerably in size. Herrings 
are exceedingly active and graceful fish, and were 
first domesticated at the Brighton Aquarium, and 

P 


210 FISHES FOR THE MARINE AQUARIUM. 


specimens are there to be seen which have been living 
in confinement nearly three years. The sprat is a 
different species, although formerly regarded as the 
young of the herring. It is even more difficult to 
keep under artificial conditions than the latter fish, 
although it has been successfully effected at Brighton, 
Manchester, and elsewhere. The pilchard is annually 
taken in immense quantities off the Cornish coast, 
but few of them are consumed in England, Italy 
being the market for them. In its young state it is 
known as the “ sardine,” and in that condition is 
imported into this country, preserved in oil, in the 
well-known tins. The specimens in the Brighton 
Aquarium were caught off the Sussex coast, for some¬ 
times the pilchard strays along the south-eastern 
and eastern coasts. Just now it is being discussed 
whether adult pilchards preserved in oil, like sardines, 
could not be turned to home use, so as to give us 
an additional food-fish, and one that could not fail 
to be appreciated. The adult fish is said to be quite 
as good when cured and preserved in this way, as 
the young, or sardine. 

The whiting and cod are both good aquarium 
objects, and are almost as familiar to the general 
public as herring and mackerel. We may find them 
in all public aquaria. The former (Gadits merlangus ), 
like the cod, is gregarious in its habits, and is said 
to be quickly accustomed to confinement. It is ex¬ 
ceedingly pretty to see them gracefully making the 


COD AND WHITING. 


211 


circuit of their artificial home, their silvery flanks 
catching and reflecting the subdued light like mirrors. 
The pollack whiting (Gadus pollachius) is a nearly- 
allied species, exhibited at the Crystal Palace, South- 
port, and Brighton. This species is more solitary in 


Fig. 139. 



Pollack Whiting (Gadus pollachius). 


its habits, and more beautifully coloured with rich 
yellow. The whiting pout (Gadus luscus ) is also 
kept at the Crystal Palace, Southport, and Brighton. 
Those at the latter place are remarkably tame, and 
will take their food from the attendant’s hands. The 
natural habitat of this fish is among the rocks, 
whence its other name of “ rock whiting.” 

The codfish (Gadus morrhuci) is nearly related to 
the foregoing, but attains a much greater size, some 
having been taken weighing sixty pounds. As is 
well known, it is an exceedingly prolific fish, Mr. 
Frank Buckland giving as an example one specimen 
in which the removed roe weighed seven pounds and 
three-quarters, and was calculated to include nearly 
seven millions of eggs. From aquarium experience 
it has been discovered that Professor Sars was right 

P 2 



212 FISHES FOR THE MARINE AQUARIUM. 

in his surmise that the spawn of the cod was not 
deposited along the bed of the sea, as was formerly 
believed, but floats on the surface of the water during 
the entire period of its development, which occupies 


Fig. 140. 



Codfish [Gains morrhua). 


about sixteen days. In the Crystal Palace and Brighton 
Aquaria this spawning has repeatedly taken place, 
and many important investigations have there been 
made in the embryology of the young fish. On 
account of its great prolificness, it is one of our 
commonest and best sources of fish-food, and it is 

































THE BEARDED ROCKLINGS . 


213 


highly important we should do all we can to keep 
it such. Its chief food is marine worms, small Crus¬ 
tacea, and small mollusca; and the carapaces and 
shells of the two latter may be found in its stomach 
in every stage of decomposition and dissolution. The 
cod becomes very tame in confinement, and is said 
even to manifest signs of attachment to those who 
feed it. The three-bearded rockling (Motel/a tricir- 
rata), as well as the four and five-bearded rocklings, 


Fig. 141. 



Three-bearded Rockling (Motella tricirrcita). 


are not distantly related to the cod and whitings. 
They take their popular names from the barbules 
which hang from the lower jaws, and which are pos¬ 
sessed by the cod family generally. All of them are 
nocturnal in their habits, and one of them, the five- 
bearded rockling ( Motella mzistela) builds a nest for 
her eggs in the crevices of the rockwork, made up 
of corallines, sea-weeds, &c. The haddock (Gadus 
cegelfinus) is another well-known species of cod, now 
to be seen in some public aquaria. The coal-fish 
(.Merlangus carbonarius) is so named from the black 
colour it frequently assumes. It is abundant in the 




214 FISHES FOR THE MARINE AQUARIUM. 


Baltic and the northern seas, and to the inhabitants 
of the Orkney Islands its young are the chief food. 
Among the Irish and Scotch fishermen it goes by a 
variety of names. It is a great enemy to salmon 
smelts as well as to young herrings, as many as 



Fig. 142.—Coal-fish (Merlangus carbonarius). 



Fig. 143.—Grey Mullet (Mugil capito) % 


twenty-six salmon fry having been taken from the 
stomach of a single coal-fish. 

The grey mullet (Mugil capito ) is another familiar 
food-fish, domesticated in most aquaria. Not un- 
frequently it will leave the sea water for a short 












GREY MULLET. 


215 


period, and ascend a river, like a salmon. Possibly 
this irregular act on the part of the grey mullet and 
some other fish may be to get rid of superfluous 
parasites, for the fish always return apparently better 
for the change. This fish has been a deserved 
favourite at the table since the time of the Romans. 
Its food mainly consists of dead and decaying vege¬ 
table matter, eked out occasionally by worms, small 
crustaceans, mollusca, &c. It is very fond of browsing 
on the green confervae in the tank, hence it is a valu¬ 
able vegetable scavenger in aquaria. Not unfre- 


Fig. 144. 



Black Sea-bream [Cantharus griseus). 


quently it attains a weight of fifteen pounds, although 
its average length is about eighteen inches. The black 
sea-bream (Cantharus griseus) is another handsome 
aquarium fish, possessing a bright silvery hue, and 
remarkable for its delicate spreading pectoral fins. 






21 6 FISHES FOR THE MARINE AQUARIUM. 

Its popular name is derived from the singular change 
which affects the male at the breeding season, when 
the silvery scales are overspread by a sooty blackness. 

As a matter of course, that magnificent fish the 
sturgeon (.A ripenser sturio) is to be seen alive at the 


Fig- 1 45 - 



Sturgeon (Acipenser sturio). 


Manchester, Brighton, and most public aquaria of 
importance. One at Manchester was nearly g feet 
in length and 4 feet in girth, and was the biggest 
introduced. It became excited, however, at the 
smallness of the space allowed it, in comparison to 





























GANOID FISHES. 


217 


the freedom of its natural habitat, and so died soon 
after its introduction. Its successor was somewhat 
smaller, but is alive at the time we are writing. 
Much the same luck occurred to the first Brighton 
sturgeons. This fish belongs to that ancient family 
the Ganoids, although, unlike one division of them, 
it is not completely clad in bony armour, but has 
four rows running along the body, and one large row 
along the medial line. Its name of “ royal ” is derived 
from an unrepealed Act of Edward II., whereby this 
fish become the property of the sovereigns of England. 
Like the salmon, it can live in fresh as well as salt 
water, and, in the north, where it attains an enormous 
size, it is usually found in the large estuarine rivers. 
The well-known substance called “ caviare ” is pre¬ 
pared from the roe of the sturgeon. The sterlet 
{Acipenser rutheorus') is also exhibited at the Man¬ 
chester and Brighton Aquaria. This fish was formerly 
believed to be the young of the former, but it is now 
known to be a distinct species. Its five rows of bony 
plates occupy much the same position, and it also 
resembles the royal sturgeon in its general habits. 
This species is very common in the river Volga. 

The pipe-fishes ( Syngnathidce ) have long been 
favourites in aquaria, and some of the species are 
kept in all our public institutions. Like their rela¬ 
tives the sea-horses (. Hippocampus ), the entire sur¬ 
face of their bodies is covered with angular bony 
plates, so that they can be kept without stuffing 


218 FISHES FOR THE MARINE AQUARIUM . 

after death, and not lose their shape. The largest 
is the great pipe-fish (Syngnathus acus), which never 
exceeds 18 inches in length. All the pipe-fishes 
swim in a nearly vertical position, with their bodies 
very rigidly disposed, and locomotion is effected al¬ 
most entirely by the very rapid undulation of the 
pretty dorsal fin. Their colour is usually palish brown, 


Fig. 146. 



Deep-nosed Pipe fish -{Syngnathus typkle). 


but they are marked by dark brown bands. All of 
them love to hide among the beds of “sea-grass” 
(Zostera marina, a true flowering plant, and not a 
sea-weed), although their food consists of the smaller 
Crustacea, for they cannot take much of any other on 
account of the peculiar structure of their mouths, 
though they sometimes eat their own young. The 
diameter of the body of the great pipe-fish rarely 
exceeds half or three-quarters of an inch. The slender 
upper and lower jaws are united, and open only just 
in front. The different species of pipe-fish are easily 
recognised by the variations in the head and tail. In 


PIPE-FISHES. 


219 


some the latter has no caudal fin, and the tail is then 
prehensile, like that of the Hippocampi, or “ sea-horses.” 
In others it expands into a beautiful fan-like object. 

As these fishes move about solely by means of the 
dorsal fin, and not by inflections of the body, the 


Fig. 147. 




Head and Tail of Broad-nosed Pipe-fish (Syngnathus typhle). 


Fig. 148. 



Head and Tail of Great Pipe-fish (Syngnathus acus). 


reader may form some idea of their graceful and 
gliding movements in the water. One of them 
(Syngnathus cequoreus) has been seen swimming far 
out at sea, whence its name of the “ Oceanic Pipe- 










220 FISHES FOR THE MARINE AQUARIUM. 


fish.” The most singular feature about these pretty 
creatures, however, is that the male fish is provided 
with a pouch, formed by an infolding of the skin of 
the lower surface of its body. Into this pouch the 
female deposits her eggs, which are there fecundated 
by the male and carried about by him, kangaroo- 
fashion, until they are hatched ! It is not true, how- 


Fig. 149. 



Head and Finless Tail of Oceanic Pipe-fish (Syngnathus cequoreus ), 

nat. size. 


Fig. 150. 



Head and Finless Tail of Syngnaihus anguineus . 

ever, that the young fish return to this pouch for 
shelter, as has been stated ; the analogy to the 
marsupial animals being there carried too far. The 
one species of sea-horse rarely found in British seas is 
usually to be seen in the same tanks as the foregoing, 
in company with a Mediterranean species. Their 
popular name is derived from the striking resemblance 
of the outline of the head and neck to those of a 






SEA -HORSES. 


221 


horse. The two species are Hippocampus brevirostris 
and //. ramulosus , the latter much rarer than the 
former. At first there was experienced a great diffi¬ 
culty in getting proper food for these objects, but it is 
now partly overcome. Their tails are prehensile, and 
may be seen twisted round some coralline or other 
marine object. They seem to possess the means of 
communicating with one another by means of sound, 
according to the observations of Mr. Saville-Kent at 
the Manchester Aquarium, where one species has 
bred.* These communicating sounds 
are short, snapping noises, produced by 
a complex muscular contraction and 
sudden expansion of the lower jaw. 

When moving about, the sea-horses 
employ only their transparent, fan¬ 
shaped, dorsal fins, which work them 
along on the principle of the screw-pro¬ 
peller, the movement being quite ryth¬ 
mical, owing to each of the fin rays 
striking the water in succession. Its Sea-horse 
favourite food is the minute opossum ^blivirostfis) 
shrimp {Mysis chameleon ), and this it 
will give chase to in a very stately fashion, uncoiling 
its prehensile tail, and moving towards its prey by 
means of the propelling action of the dorsal fin, with 
never-failing dexterity. When within half an inch of 

* Upwards of a thousand young Hippocampi were recently bred in 
the Southport Aquarium. 



222 FISHES FOR THE MARINE AQUARIUM. 


the opossum shrimp it opens its mouth, and inflates 
its cheeks so as to cause an in-rush of water, down 
which the unfortunate crustacean is engulphed. The 
opossum shrimp may be seen swarming in the water 


Fig. 152. 



Opossum Shrimp [Mysis chameleon ). (Three times natural size.) 

Fig. 153 - 



of most rock-pools. It is a queer little object, with 
the very singular peculiarity of being able to hear by 
its tail, at the base of which are certain cavities filled 
with crystalline otoconia , or “ ear-bones.” 





FLA T-FISHES. 


223 


The well-known “ flat-fishes,” such as the sole, dab, 
flounder, plaice, brill, turbot, &c., are in strong force in 
all our large marine aquaria, where they attract much 
attention on account of their unexpected graceful 
movements in the water. It is only there that we 
can thoroughly understand the marvellous changes 
which have been effected in the life-history of these 
fishes, by means of which both their structure and 
habits have been slowly adapted to their present 
condition. Their popular name of “ flat-fishes ” is apt 
to lead one astray in his conclusion as to the cause 
of this flatness. It is not due to the fishes lying 
with the belly or ventral side downwards; but to 
their habitually lying on one side. They are com¬ 
pressed ' not depressed , as in the skates. Then only 
one side is coloured, that next the ground being very 
light. But the coloured part is usually called the 
‘‘back,” whereas we now see it is only a special 
adaptation to the really wonderful modifications these 
animals have experienced. Moreover, the observer 
may notice how soles and other flat-fishes having 
a uniform dull neutral tint usually settle down on 
the sandy part of the bottom of the tank, and add 
still further to their concealment by dusting them¬ 
selves over with the fine sand, which rises and partly 
settles down over them, so as to form an admirable 
screen. Such flat-fishes as the plaice, on the other 
hand, will be often seen to select that part of the 
bottom where gravel is abundant; and then we may 


224 FISHES FOR THE MARINE AQUARIUM. 


notice the meaning of the ochreous or yellow spots 
distributed over the surface of one side of such fishes. 
They simulate the bright pebbles, and help to conceal 
the fishes from their enemies. 

In the plaice (Pleuronectes platessa), and sole (Solea 
vulgaris ), the coloured or upper surface is the right 
side; whilst -in the turbot (Rhombus maximus) it is 
the left. In both cases, whether the upper side be 


Fig. 154 - 



The Flounder (Pleuronectes flesus ). 


right or left, the eyes are turned round so as to be 
placed on the upper side. When swimming in the 
water the same abnormal position is adopted, the 
fishes swimming on their sides, and not erect, after 
the usual manner. The apparent, not real, motion of 
the tail and whole body is also horizontal, instead 
of being vertical. There can be no doubt whatever, 
to the philosophical zoologist, that all the flat-fishes 
have been, in course of time, modified from the ordi¬ 
nary and more symmetrical type of fish. Even now, 





monstrosities in fish. 225 

we occasionally get what is termed a “ monstrosity,” 
in which a flat-fish has its eyes one on each side— 
this being a reversion to the ancestral type. During 
the earliest stages of all flat-fish within the egg they 
are like ordinary fishes ; as they develop, one eye 
may be seen gradually turning round to the same 


Fig- 155 * 



The Brill {Rhombus lcevis ). 


side as the fixed one, and in this way we have a 
flat-fish, modified to swim and rest on one side, and 
perfectly adapted to live under what seem the most 
singular conditions we can imagine of any animal! 
The skull partakes of the same embryological modifi¬ 
cation, being symmetrical when the fish is in the 
egg, and gradually changing to an unsymmetrical 
state as the fish gets older. Some of the flat-fish 
attain a great size, especially the halibut, turbot, 
and brill; whilst others, as the little dab (Platessa 

Q 
















226 fishes for the mar/he aquarium. 

limanda ), never acquire great size or weight. This 
graceful fish must be seen alive in the tanks to be 
properly admired. There are several species of dab, 


Fig. 156. 



The Dab {Platess a limanda). 

but the above is the commonest. The specific name 
of limanda is derived from the Latin word for a “file/’ 
in allusion to the roughness of the scales on the 
upper side. All the flat-fishes live on small rnoiiusca 
and Crustacea, alive and dead. 





















































































JOHN DORY . 


227 


In addition to the fishes mentioned in the last three 
chapters, which practical experience has proved may 
be more or less readily acclimatised in marine 
aquaria, there are many others, and the list is 
being added to almost every week. The conger-eel 
{Conger vulgaris) ; john dory {Zeus faber), a lovely 
fish when alive, whose common name is corrupted 
from the French jaune doree, an apt allusion to 
its burnished golden body; the fork-beard {Raniceps 
trifurcatus ) ; the singular gar or guard fishes {Belone 
vulgaris) f whose slender elongated, silvery body 
terminates in formidable jaws, armed with sharp 
teeth; the mud fish—a singular illustration of the 
“ missing links” between amphibians and fishes ; the 
lovely and graceful smelts ; sting rays ; sur-mullets ; 
skates of all kinds, &c., are among the commoner 
kinds exhibited alive. The study of marine fishes is 
now removed from the mere examination of dried 
skins or shrunk specimens preserved in spirits, to where 
they can be seen in their natural element, graceful as 
butterflies in their motions, and many of them hardly 
less brilliantly coloured. There we can watch out 
every stage of their life-history, from the extrusion of 
the spawn to the adult fish, and can understand from 
their habits of life the meaning of many a structural 
peculiarity, many a tint and spot and ornament, which 
before we should have rashly assigned to some freak 
of Almighty Power, unaware that we were then exer¬ 
cising a mental act that savours of blasphemy! 

Q 2 


223 


CUTTLE-FISH , MOLLUSC A, ETC . 


CHAPTER XIV. 

CUTTLE-FISH, MOLLUSCA, ETC., OF MARINE 

AQUARIA. 

In all our large marine aquaria no object has been 
more popular than the octopus, or “ devil fish,” as it 
has been more emphatically called. The weird stories 
told of it by Victor Hugo, in his ‘Toilers of the Sea,’ 
had prepared the public mind for something so ex¬ 
ceedingly ugly as to be unusually attractive ; and 
accordingly the first specimen of a living octopus 
in the Crystal Palace Aquarium had to bear the 
uninterrupted gaze of lookers-on for weeks. It sat 
for its portrait in the illustrated papers, and had all 
its points noted down by newspaper correspondents 
with the same faithful detail as if they were those 
of prize cattle at the Agricultural Show. Brighton 
afterwards became possessed of one of these animals, 
and fortunately Mr. Henry Lee was there to study 
its habits, and to embody them in a series of papers 
which were collected into a volume not long ago on 
‘ The Devil Fish of Fiction and of Fact.’ This is the 
most interesting work on the cephalopoda we have 
in our language. 

Since Victor Hugo so largely drew upon his vivid 


CUTTLE-FISHES. 


229 


imagination in the description of his peculiar species 
of cuttle-fish (or “cuddle’’-fish, from the powers 
of embracing possessed by its long arms), portions of 
gigantic specimens have been found off the coasts of 
Newfoundland, and described in the scientific journals. 
These fragments indicate the actual, but fortunately 
rare, existence of cuttle-fishes nearly 30 feet in length, 
arms included. The old fishermen’s stories of boats 
being sometimes enveloped by the arms of these huge 
* krakens,” have a semblance of truth. The common 
octopus (Octopus vulgaris) is now kept in all our ma¬ 
rine aquaria. Its structure is very peculiar, for the 
water admitted into a special chamber for aerating 
purposes, can be so expelled as to subserve the 
purpose of locomotion. The animal usually crawls 
along the sea-floor head downwards, moving about by 
means of its long tentacles. But when it wishes to 
move more rapidly, all these are drawn together in front 
of the head, the water is jerked out of the branchial 
chamber through a special funnel, and the cuttle-fish 
is thus driven backward by the rebound. The suckers 
on the tentacles are most formidable organs for re¬ 
taining hold, each one being provided with a natural 
piston, so that a vacuum can be created when it is 
withdrawn at the will of the animal. The horny 
mandibles of the mouth are very much like those of 
the parrot, and by their means the cuttle-fishes can 
bite through the carapaces of the crabs, &c., on which 
they habitually feed. Although this species pos- 


230 


CUTTLE-FISH , MOLLUSC A , £ 7 Y 7 . 


sesses an ink-bag its contents are rarely poured forth ; 
but when alarmed, the ink-bag is emptied suddenly, 
and the water is then so beclouded with the inky 


Fig. 157. 



“ Devil Fish ” (Octopus vulgaris )» 


Fig. 158 



Homy jaws, or mandibles of Cuttle fish. 

fluid that the cuttle-fish can make its secure escape 
whilst the water is disturbed. The octopus has the 
peculiar power of changing the tints of its skin, ac¬ 
cording to those of the ground it may be reposing 





SEPIAS AND SQUIDS. 


231 


upon ; for its habits are not very active, and it will 
remain in the same position for hours, occasionally 
coiling and uncoiling one or another of its eight long 
sucker-clad feet or tentacles. A stock of live shore- 

Fig. 159. 



Common Sepia {Sepia officinalis ). Bone of Common Sepia 

{Sepia officinalis ). 


crabs (Carcinus mcenas) is usually kept in a separate 
tank for the purpose of feeding cuttles. 

The common sepia (Sepia officinalis ) is also kept 
under artificial marine conditions, but it is not so 






























232 CUTTLE-FISH MOLLUSCA, ETC. 

great a favourite, either with the public or the ma¬ 
nagers, on account of the readiness with which it 
discharges the contents of the ink-bag, so as to dis¬ 
colour the water of the tank. This species is a 
decapod, not an octopod—that is, possesses ten feet, 
of which two are long and retractile, instead of eight, 
as in the octopus. The so-called internal “bone” of 
the sepia is a common object along our coasts, where 


Fig. 161. 



Sepiostaire (ground plan). 
(Magnified.) 



Sepiostaire (vertical section). 
(Magnified.) 


its whiteness soon attracts attention. Of course in 
this condition it represents a once living animal, just 
like any other skeleton does. These “bones” are 
termed u sepiostaire,” and are collected and ground up 
for tooth-powder, the calcareous matter retaining its 
crystalline structure to the smallest particle, and thus 
being an admirable dentifrice. Slices of the sepio¬ 
staire, both vertically and horizontally, make beautiful 
objects for the microscope, and show the mode in 










BONES OF CUTTLE-FISHES. 


233 


which it is built up. The common squid (Loligo 
vulgaris) is also a decapod, two of its tentacles being 
much longer than the rest. Like the sepia and others 
of the same group, it possesses an internal bone or 



Common Squid Pen of ditto. 
{Loligo vulgaris ). 


“pen,” the latter name being given to it on account 
of its semi-transparent horny or quill-like structure. 
This “ pen” contains no limey matter. The Sepiola 
Rondeletii is a much smaller cuttle, and addicted to 
roving habits. It is not uncommon as an aquarium 























234 CUTTLE-FISH , MOLLUSC A, ETC. 

object, although it gives some trouble through its 
ink-discharging habits. Besides the above-mentioned 
species, another octopus (Eledone cirrhosa ), having 
only one row of suckers on its feet, is kept in most of 
our public aquaria. 


Fig. 164. 



Sepiola Rondeletii. Pen of ditto. 


Although the cuttle-fishes and their allies are un¬ 
doubtedly at the head of the mollusca—a position 
warranted by their specialised and perfect organs of 
sight, brain (enclosed in a cartilaginous box, sug¬ 
gestive of a skull), mouth, stomach, locomotive powers, 
&c.—they belong to one of the most ancient groups, 
geologically speaking. We meet with some of their 
ancestors in the Cambrian strata; although the recent 
type of cuttle-fish, with the hard parts internal in- 







MARINE UNIVALVES . 


235 


stead of externa], dates back no further, perhaps, than 
the oolitic epoch. 

Shell fish, both univalve and bivalve, are kept 
in aquaria, according to their habits; although the 
limpet, chiton, fissurella or “ key-hole limpet,” dog- 
whelk, and periwinkle are peculiar to shallow waters, 

Fi s- l6 S- Fig. 166. 



Animal of Fissurella. 


Key-hole Limpet 

{Fissurella Grceca). 


and will creep out into the air. These are most 
of them easy of domestication in such shallow tanks 
as an amateur would commence with. All are in¬ 
teresting objects, the limpet family, including the 
several species of chiton, being particularly so. The 
latter looks like a woodlouse, and has the power 
of partially coiling itself up when detached from 
the rock, to which, however, it clings as long as 
it can with all the proverbial force of a limpet. 
Formerly it was called a “ multivalve ” shell, on 
account of this latter being made up of a number 
of transverse pieces. It is, however, a near rela¬ 
tive of the limpet. Their young are shell-less, and 
have a semi-ring of cilia around the margin of the 



236 CUTTLE-FISH , MOLLUSC A, ETC. 

upper half, by means of which they can swim about 
freely. The handsomest of our British chitons, per¬ 
haps, is Chiton fascicularis , so called on account of the 
bundles or tufts of bristles which crop out between 
the plates. This species crawls backwards and for¬ 
wards with equal facility. The key - hole limpet 
(Fissurella Grceca ) is tolerably abundant around the 
more southerly shores of Britain. 

Fig. 168. 



Egg-cases of White Whelk. 


The white whelk ( Buccinum undatum) as well as 
the red whelk ( Trophon antiquum) is a good aquarium 
object, active and vigorous in its movements; and 
may be useful for devouring any decomposing animal 
matter. The white whelk is usually caught by lower¬ 
ing pieces of decaying fish or flesh in shallow places ; 
the whelks soon scent these out, and crowd over them 
in immense numbers, and are then caught by hoisting 
up the fragments to which they are attached. In the 
eastern counties these molluscs are largely eaten, and 
with good reason, for their flesh is so much like that of 
the edible cockle that it might easily replace it as a 






EGGS OF MOLLUSC A, 


237 


culinary object. The egg-cases of the whelk are very 
common objects by the seaside, of a light brown 
colour, resembling a large head of hops. Each capsule 
contains an individual embryonic shell, perfectly 
formed, and not exceeding a pin’s head in size. When 
they are present in a storm-tossed specimen of egg- 
cases, they are detached, and rattle inside the cap¬ 
sules when shaken. Haliotis tuberculata or “Venus’ 
ear,” is another marine mollusc of much service in 
the aquarium as a vegetable scavenger. It is lively 
and attractive both on account of the graceful shape 
of the animal, and the parasitic weeds which adorn 
the shell. Nassa purpura (or dog-whelks), top 
shells ( Trochi), murex, Pileopsis , Cyprea , Aporrhais 
pespelicani (or pelican’s foot shell), Natica monilifera 
—a common and prettily marked univalve shell, 
easily domesticated— Turitella , Bulla , &c., are other 
univalves which are kept with more or less ease in the 
Brighton, Crystal Palace, and Manchester Aquaria. 

The group of shell-less molluscs—answering in the 
sea to the slugs upon land—have been favourites in 
the marine aquarium ever since Alder and Hancock, 
and especially Gosse, wrote so attractively about 
them twenty-five years ago. But the sea-slugs breathe 
by means of gills, which are usually borne on the 
back, uncovered by any shell, hence the name given 
to the group of Nudibranchiata , or “ naked-gilled.” 
These branchiae or gills are usually coloured, or 
prismatically tinted, so as to render their possessors 


238 


CUTTLE-FISH , MOLLUSC A, ETC. 


very beautiful and attractive objects. In another 
group ( Tectibranchiatd ) commonly to be seen in ma¬ 
rine tanks is the Aplysia> or “ sea-hare ”—so called 
on account of the rude resemblance of the head and 
shoulders to those of a “ sitting hare.” The Doris , or 


Fig. 169. 



Sea-slug (ALolis coronata). 

( X 

“sea-lemon,” well deserves its popular name both 
from its colour and general appearance. These sea- 
slugs usually construct very pretty “ nidal-ribbons,” or 
egg-cases, in which the eggs are placed in thick rows, 
like beads closely stitched over the surface of a piece 
of ribbon. 

Among the bivalves, we cannot wonder that the 
oyster and the mussel are favourites. The latter is 
abundantly kept in the tanks, on account of its enor¬ 
mous powers of reproduction. The issue from a 
single living specimen would soon multiply at such a 
rate as to clothe the entire surface with dense masses 
of mussels ; but the young are greedily sought after 
by many fishes, &c., so that they are advantageously 


BRITISH MUSSELS. 


239 


placed in tanks where their reproductive powers can 
be turned to account in feeding the other objects. 
We have several British species of mussel, the prettiest 


Fig. 170. 



Common Mussel (Mytilus edulis). 


Fig. 171. 



Common Mussel, laid open to show the plated gills. 


of which is that called the “ tulip mussel,” a variety 
of the common mussel, on account of the petal-like 
stripes of colour which streak the shells. The com- 







240 


CUTTLE-FISH, MOLLUSC A, ETC. 


mon mussel (Mytilus edulis) is one of the most fertile 
of all mollusca, and this natural history fact has 
been turned to greater practical account off the French 
coasts than off our own. It is capital food, especially 
when fresh, and as such is cultivated off the Nor¬ 
mandy coasts, as we cultivate oysters, and thence im¬ 
ported into the interior in immense quantities as food 
for the working people. Off the Norfolk coasts the 
mussel banks which form there so rapidly are used 
chiefly for manuring the land. The so-called “ moss ” 
is in reality the byssus, or anchoring threads, and has 
nothing poisonous about it, although this part has 
been credited with producing the painful affection 
known as “ musselling.” We believe, however, that 
the latter is due to partaking of decomposing mussels, 
some of which are apt to get into every measure of 
them, from the way some of the fishmongers have of 
mixing up their old stock with the new. In this way 
a very old and rotten specimen may be made to taint 
and infect all the rest during the process of boiling 
and preparing for the table. 

Oysters are never likely to lose their interest to 
people who care anything at all for the pleasures 
of the table; and our aquaria have already con¬ 
tributed some important facts concerning oyster 
culture. Apart from their well-known and highly- 
esteemed edible qualities, they are favourites with 
managers of large marine aquaria from their useful¬ 
ness in clearing turbid sea water, and rendering it 


YOUNG OF OYSTERS. 


241 


transparent. Mr. Lloyd believes this is due to their 
breathing out quantities of carbonic acid gas, and thus 
converting the carbonate of lime which gave the water 
a milky appearance, into a ^/-carbonate, when the 
visible carbonate is taken into suspension and thus 
rendered invisible. Oysters are therefore to be seen 
distributed in nearly all the Brighton tanks, on ac¬ 
count of the temporary service they render in keeping 
the water transparent. Their semi-opened shells 
exhibit the plates of gills (commonly called the 
“ beard ” of the oyster). These gills are richly clothed 
with active cilia, which create currents in the water, 
and thus the gills are constantly bathed by fresh sup¬ 
plies of oxygen, the same currents also bringing food. 


Fig. 172. 



Young Oysters, with their natatory or swimming gills. 


A good deal of the turbidity of sea water in tanks 
is often due to the presence of myriads of the 
zoospores of algae. These zoospores have a wrig¬ 
gling motion, so that few people uninstructed in 
the life history of sea-weeds, would imagine them to 
be connected with the- reproductive parts of maritime 

R 


242 CUTTLE-FISH , MOLLUSC A, ETC. 

plants. No doubt these zoospores form a good part 
of the food of such sedentary mollusca as oysters, 
mussels, &c. 

The young of the oyster do not leave the folds of 
the mother until they are capable of moving about 
and seeking their own food. At first, therefore, oysters 
are free-swimming, moving about by means of special 
tufts of cilia. A single oyster will throw out myriads 
of such embryos, which go by the name of “ spat.” 
In many respects these very young oysters resemble 
the lower Crustacea, the Entomostraca , for like them, 
they have two shells, through which the natatory 
gills are protruded. When the young oysters settle 
down to the same staid life as their parents, the spat 
is then said to “ fall.” In from one to three years, 
according to circumstances, they will have reached 
the adult stage. At the Crystal Palace the Ame¬ 
rican clam ( Cyprina moneta) is shown alive. Indeed, 
there are few bivalves which cannot be healthily 
kept in aquaria, especially if the conditions are 
right. Two species of cockle, the edible and the 
spiny ( Cardium edule and C. echinatuiri), may usually 
be seen in tanks. The burrowing and leaping habits 
of the cockles are very interesting to witness. The life 
of the young of the common species is very much like 
that of the oyster. The recurved spines of Cardium 
echinatum are bent in a direction contrary to that in 
which the animal burrows, so that they do not impede 
its habits. All the species of scallop-shells {Pecteri) 


SCALLOPS AND PHOLADES. 


243 


move by means of alternately opening and closing the 
flattish shells with a kind of jerk. This enables them 
to dart backwards to some distance; and, as some of 
our British species have very richly coloured shells 
(especially those obtained off the 
south-eastern coasts), it follows 
that they have a butterfly look 
when seen in the water. Around 
the edge of the mantle, through 
the partly opened shells, may be 
seen a row of eyes, looking like 
diamonds set in a ring, except 
that the latter can give no idea 
whatever of the depth of colour Scallop ( Pecten ). 

and play of light which these eye-spots of the Pecten 
seem to contain. 

The burrowing powers of some bivalves is not 
limited to sand or mud. We find them able to 
excavate a protection for their fragile shells in the 
hardest rocks ; limestones, however, being evidently 
preferred to any other. The Pholas , Saxicava , 
Teredos , and others, are able, nevertheless, by means 
of the rough thick part of these shells, near the hinge, 
to mechanically excavate the holes in which we find 
such mollusca living. The mode in which these 
holes in rock were formed was discovered by keep¬ 
ing pholades in an aquarium, by Mr. Robertson of 
Brighton, who carefully watched the entire process 
and wrote a detailed account of it. These holes are 

R 2 






244 


CUTTLE-FISH , MOLLUSCA, ETC. 


always widest at the bottom, and narrow at the top, 
which communicates by means of a fleshy syphon or 
tube with the external water. 

Fig. 176. 



In some bivalves these syphons are double, as in 
the sand mussels (Mya arenarict and M. truncate :) ; a 
current of fresh sea-water goes down one, and the 
water, after passing the gills and mantle, and being 
partly deprived of its organic matter and oxygen, is 
returned up the other. These mussels burrow in mud 
and sand, so that little is seen of them except the tips 











SHIP WORMS. 


245 


of their coalesced syphons, which are covered with a 
fringe of cilia that guard against the entrance of 
unsuitable matter. Both species of these common but 
elegant shells are kept in our public aquaria. In ad¬ 
dition to the stone-borers ( Saxicava and Pkolas) at 
the Crystal Palace may be seen the wood-boring 
mollusca ( Xylophaga and Teredo). The latter goes 
by the common name of “ ship worm,” but it is in 


Fig. 177. 



Mactra stuitomm. 


reality a mollusc in which the shells are reduced to a 
minimum of size, the lime secreted by the animal 
being used to line the winding worm-like burrows it 
makes in the wood where it takes up its abode. The 
Madras , Tellmas , Donax, and Venus are other prettily- 
coloured and elegant aquarium mollusca. Cyprina 
islandica , Modiola , Modiolus (the latter usually called 
the “ horse-mussel”), Pinna pedinata , Lima hians, 
Scrobicularia piperata , &c., are many of them larger 



246 CUTTLE-FISH , MOLLUSC A, ETC. 


in size, but all have been or are kept in captivity at 
the Crystal Palace. At Brighton, some of them, as 
well as species of echinoderms, appear to be kept with 
great difficulty, or cannot be preserved at all. 


Fig. 178. 



Donax folitus. 


Around the margins of the rockwork in most of the 
large marine tanks may be seen rows of greenish- 
white objects, not unlike elongated white Hamboro’ 
grapes, which are fixed by their bases. These are the 
Ascidia, a very interesting group of mollusca allied 
to the polyzoa, which some naturalists have actually 
included among the Vertebrate animals. For reasons 
which are partly structural and embryonic, they are 
usually regarded, however, as nearly related to the 
mollusca. They are in reality soft-coated mollusca, 
just as oysters and others are hard-coated. Four 
species of these ascidians, Ascidia intestinalis , A. 
vitrea, Molgula tubu'losa , and Cynthia quadrangular is, 
have semi-spontaneously made their appearance in 




THE ASCIDIANS. 


24 7 


the marine tanks of the Crystal Palace, Brighton, 
and elsewhere. They are pretty objects, increasing 
at an abundant rate. The embryos of some of them 
(notably the Cynthia , commonly known as the “ cur¬ 
rant squirter ”) are free-swimmers, and have a peculiar 


Fig. 179. 



Ascidia mentula. 


tadpole-like appearance. Among fishermen all the 
ascidians go by the popular name of “sea-squirts,” 
from the ease with which they can eject a jet of 
water when their leathery outer tunic contracts; 
hence their name of Tunicata, These peculiar, and 
to the philosophical naturalist most interesting, 






























248 CUTTLE-FISH , MOLLUSCA , ^TT. 

animals, are not distantly related to other marine 
objects called “ sea-mats,” whose dry brown fronds 
are frequently to be picked up along the sea-coasts, 


Fig. 181. 



where they are usually mistaken for sea-weeds, and 
mounted as such in albums. They are. however, 
colonies of really highly organised individuals, of 






POLYZOAN COLONIES. 


249 


microscopic smallness, which live as neighbours in 
the horny frond they have secreted in common A 
magnifying glass will show that the surface of such 
frond is covered with cells, all shaped alike. In 
these the polyzoans live, obtaining 
fresh air and food by means of their 
cilia, which are protruded so as to 
be constantly agitating the water. 

These sea-mats may be kept alive 
in small aquaria, when even by the 
naked eye we can perceive the ex¬ 
trusion of the cilia by the filmy 
bluish-whiteness which seems to 
come over the surface of the frond. 

Each individual of the colony form¬ 
ing the sea-mat lives separately 
from the rest. In this respect, 
therefore, they are utterly unlike the Sertularians , or 
“sea-firs,” in which the individual polpes are con¬ 
nected by a common flesh which runs up the horny 
stem, and is given off to every branch so as to be 
connected with every zoophyte. Moreover, the ani¬ 
mals forming the sea-mats have a nervous system, 
which the sea-firs have not, as well as a more complex 
physiological organisation. Some of the members 
of this family may be seen encrusting sea-weeds 
with a most delicate white lace-like tracery — the 
lace-work being produced by the cells of the animals. 
The commonest of these is Membranipora pilosa , 


Fig. 182. 



Magnified portion of 
Fiuslra. 










































250 


CUTTLE-FISH, MOLLUSC A, ETC . 


which may be found wherever sea-weeds are to be 
gathered, clustering their stems or spread out over 
the fronds. It is held by naturalists that the ap¬ 
pearance of sea-mats, sea-squirts, &c., in aquaria, 


Fig. 183. 



The Sea-fir {Sertularia abietina). 


is a proof that the water is in a healthy condition. 
Another allied and abundant colony of marine ob¬ 
jects—all of them having affinities with the mollusca 
in spite of their apparent differences—may be seen 
on the backs of the larger sea-weeds and other objects. 
They look like a firm layer of hardish jelly, in which 
are scattered “stars.” We have several genera and 
species of these pretty creatures, all of which are 
apt to make their appearance in healthy tanks. 
Some are joined at their bases by means of a thread- 


POLYZOAN COLONIES. 


251 


like connection ( Clavehnd) ; but those in which the 
individuals form star-like masses go by the name of 
Botryllus. This really signifies a bunch of grapes, 

Fig. 184, 



and is an allusion to the way in which the individual 
members of a Botryllus colony are related to each 
other, just as the grapes on the same bunch are. 
Each “ray” of a “star” (Fig. 186) is a separate 










252 


CUTTLE-FISH, MOLLUSCA , ETC. 


animal; but all “ are arranged in this stellate form 
because they have one anus in common, out of which 
excreta, &c., are ejected.” The mouth of each animal 
may be seen like a dot in the “ ray.” * This is sur- 


Fig. 185. 



Botryllus on frond of 
sea-weed. 


Fig. 186. 



a, Botryllus polyclas; b. Separated indi¬ 
vidual, forming a “ ray” of one of 
the star-like objects. 


rounded by cilia, and when alive, is in reality a very 
active organ, producing miniature whirlpools in the 
sea water, and thus obtaining fresh oxygen and food. 
The common anus forms the centre dot of each 

* Throughout this book such circulating currents in various animals 
are frequently mentioned, and they are now particularly adverted to, 
because it is by imitating them in the machinery of aquaria that the best 
biological results are attained. In this way, perhaps unconsciously, we 
do as Nature does, and then find that she, long previously, has done 
"he same thing in a far neater and better manner. 
































SHAPES OF ANIMALS. 


253 


“star.” We have long since learned that the mere 
magnitudes and even shapes of animals are not the 
most important characters by which to associate 
groups, but this fact is nowhere felt in such a degree 
as when we study the polyzoa and their allies. 


254 CRUSTACEA , ECHINODERMS, ETC. 


CHAPTER XV. 

CRUSTACEA, ECHINODERMS, ANNELIDS, ETC., OF 

MARINE AQUARIA. 

ONE of the most important advantages which large 
aquaria, aerated by constant jets of water, possess, 
is the great variety of marine animals, vertebrate and 
invertebrate, which may be kept in them. Not only 
may they be so selected as that one group shall not 
harm another, but much of the labour and anxiety 
likely to occur from the pollution of the water by 
decomposing food or dead animals, may be prevented 
by merely including certain omnivorous creatures 
which will clear away such garbage and consume 
it as food. Some of the carnivorous mollusca (the 
whelks, for instance) are useful in this respect, but 
many of the Crustacea are even more so. The latter, 
also, are more lively animals, and never fail to cause 
amusement by their grotesque and serio-comic habits. 
One cannot witness the rude gambols of lobsters and 
crabs without feeling that the element of humour is 
not merely a subjective condition of the human mind, 
but has an objective existence in nature. 

Of all the useful and interesting scavengers, none is 
more so than the hermit crab (Pagurus Bernhardus ) 


HERMIT AND SOLDIER CRABS. 


255 


so called from its occupying an empty shell, as a 
hermit would his cave. This crust acean is forced to 
this singular habit by the softness of its abdomen, 
which does not secrete a hard crust, and therefore 

Fig. 187. 



Hermit Crab (Pa gurus Bernhardus). 


requires such protection as an empty whelk-shell will 
afford. Nothing on earth exceeds the shamefacedness 
of a hermit crab deprived of its shell—not even a 
bather whose clothes have been stolen! When per¬ 
fectly accommodated with an empty shell, the hermit 
crab is most suspicious and wary. It regards every¬ 
thing as an enemy; and even when one of its own 
kind approaches, you will see it move away, or draw 
itself within its cave, and close the aperture by means 
of its large right claw, which is bigger than the other 
for the purpose. Being as warlike as they are sus¬ 
picious, a good ma T |iy fights come off in the tanks 
between them, insomuch that this species is also called 
the “ soldier crab.” The somewhat vulgar practice is 
now followed of introducing highly-coloured empty 






256 CRUSTACEA , ECHINODERMS, ETC. 


tropical shells for the hermit crabs to take up their 
abodes in, although this has added to the attractive 
appearance of the bottoms of the tanks. Before moult¬ 
ing these crabs generally leave their old domiciles, 
and select one so much bigger that they can move 
about in it. Their increase in bulk is then usually 
very rapid. Many a contest comes off between hermit 
crabs, when two of them wish for the same empty 
shell. Every atom of food rejected by other animals 
in the tank, and which would otherwise lie on the 
floor and foul the water, is greedily cleared away by 
hermit crabs and their allies. 

The graceful appearance of lobsters when at rest 
makes them prominent objects. They seem to be in 
almost a devotional attitude, resting on their huge 
pincers as the “ praying mantis ” does on its fore-legs ; 
and in this position are often seen with their faces 
towards the glass front. Their long, slender, jointed 
antennae are thrown backwards, and are in a constant 
state of motion. The spiny lobster, or “ sea-cray¬ 
fish ” (Palinurus quadricornis), is a more attractive 
marine object than the common lobster, although its 
flesh is not such delicate food as that of the latter. Its 
body is covered all over with spines and prickles, and 
is moreover very brightly coloured. In length this 
species exceeds any other British Crustacea. It is 
noticeable, however, by the absence of the large and 
powerful pincers which distinguish the common lob¬ 
ster. The females of this species have spawned both 


SPINY LOBSTERS. 


Fig. 188, 



Spiny Lobster, or Sea Cray-fish {Palinurus quadricorms). 
a. Left outward foot-jaw. 


S 










258 CRUSTACEA , ECHINODERMS , ETC. 


at Hamburg, Brighton, and the Crystal Palace, and the 
tanks were then crowded with transparent, leaf-like 
young, which, before then, were regarded as a distinct 
species, and called the “ glass crab ” ( Phyllosoma ). 
The common lobster (Homarus vulgaris) is an aqua¬ 
rium favourite, and although its colours are not so 
bright as those of the foregoing, the plum-tinted 
carapace is not without beauty; whilst its graceful 
motions in walking and climbing by means of its 
slender feet, and swimming either by the aid of the 


Fig. 189. 


o 



Embryo of common Lobster, magnified 20 diameters. 

“swimmerets ” arranged underneath the abdomen as 
so many fringed plates, or by one flap of the powerful 
expanded, fan-like divisions of the tail, give a good 
deal of animation to a tank. When several of these 







YOUNG OF THE LOBSTER. 


259 


Crustacea are together the interest is much increased. 
The development of the young of the lobster, from 
the numerous eggs which the female usually carries 
under her body in dense masses, has recently obtained 
a good deal of attention. It is most interesting as 
indicating the nauplius stage, which characterises the 
early embryos of nearly all crustaceans alike, no 
matter what their adult differentiations may be. 
The young of the lobster pass through several stages 


Fig. 190. 



Larval or mysis stage of the common Lobster. 


before they reach the adult condition. The first is 
visible before the egg is hatched. In this condition 
the carapace (b) is indicated by the presence of spots 
of red pigment, the rudiments of the eye (c), antennae 







260 CRUSTACEA, ECHINODERMS, ETC. 


Fig. 191. 


(d and e), of the great claws ( g ), and the bilobed 
tail ( m ), are plainly visible, as well as the most im¬ 
portant of the internal organs, such as the heart (/), 
intestines (k) } &c. On hatching, the second con¬ 
dition, called the my sis stage — because it then 

resembles the adult condi¬ 
tion of the opossum shrimp, 
or Mysis —is next under¬ 
gone. The young lobster 
is now about one-third of 
an inch in length, and, as 
will be seen in Fig. 190, 
possesses six pair of legs, 
one pair being subse¬ 
quently modified into foot- 
jaws. In the third stage, 
when the larva has at¬ 
tained a length of about 
half an inch, it loses its 
mysis -like appearance, and 
begins to assume some¬ 
thing like its adult features. 
In the mysis condition it 
swims on or near the sur¬ 
face of the water ; and even 
in the next stage is more 
or less of a free swimmer, these habits not being left 
off until after several succeeding stages of its develop¬ 
ment. At present it will be seen from Fig. 191 that 



Back view of fig. 190. 




YOUNG OF LOBSTER. 


261 


rudimentary “ swimmerets ” have appeared on the 
second to the fifth segments of the abdomen, whilst 
the large claws are in process of formation. Even 
after the young have reached what is called the adult 
stage, they are so unlike fully developed lobsters that 
they might be regarded as a different genus. Their 
movements are now very much like those of shrimps, 
and they frequent the surface of the water much more 
than the bottom. All the above changes are believed 
to take place in a single season. 


Fig. 192. 



Like all the crustaceans, thick-tested species parti¬ 
cularly, the lobster increases in size by moulting or 
casting off its old coat, which is thrown off in one 
piece, and looks so perfect that it might be taken for 
the animal itself. Not unfrequently it casts an odd 







262 CRUSTACEA , ECHINODERMS, ETC 


limb, or has one torn off in a fight. This difficulty is 
got over by a new one budding. Mr. Lloyd speaks 
of the general moulting as follows in his capital little 
‘ Handbook to the Crystal Palace Aquarium ': 

“ This moulting is necessary because the shell once 
formed never grows larger, and therefore as the 
creature within increases in size, and a new shell in a 
soft state begins to be formed below the old one, the 
latter becomes too small. The lobster is aware of 
this, and of its approaching moult, and instinctively 
knowing its utter helplessness from the attacks of its 
fellows, or from other animals during the quarter or 
half hour occupied by the disengagement of its shell, 
and while it is more or less soft for a few days after¬ 
wards, it, in an aquarium, sets about making a regular 
fortress, choosing its position with great judgment, 
usually beneath a shelving rock, with rock on each 
side, and with a kind of “ earthwork ” thrown up de¬ 
fensively in front, composed of the sand and shingle 
which have been removed from the hole in which it 
burrows, and here, ever on the watch for intruders, it 
patiently awaits its change of coat. Occasionally, when 
this fortification cannot be made, the lobster seeks a 
less perfectly protected place on a plateau of rock 
close to the water’s surface, and therefore not often 
visited by other animals. When the time at last 
comes, it throws itself on its side, and ruptures the 
skin connecting the body with the first ring of the 
abdomen, and this is the only part intentionally 


MOULTING OF LOBSTERS. 


263 


broken, though occasionally a limb is accidentally 
separated in the operation. The greatest difficulty 
seems to be in drawing the large anterior claws 
through the comparatively very small dimensions of 
the same limbs where they join the body, as, contrary 
to what has been stated in books, these large claws 
are not split open to allow of the emergence of the 
limbs. The claws are soft, however, and are tempo¬ 
rarily rendered shapeless by being pulled through 
these little orifices. After the great limbs are free, 
the rest is more easy, and by a series of spasmodic 
efforts the remainder of the legs are extricated, to¬ 
gether with the antennae, great and small, and the 
whole of the complex organs surrounding the mouth, 
and even the eyes and the breathing organs are with¬ 
drawn from their old coverings, and while this goes 
on, the tail is released. All proceeds simultaneously, 
so that while one part of the process is being watched, 
another is effected unobserved. When everything is 
at last free, the lobster lies as if dead, and occasionally 
does die from exhaustion, but generally it slowly 
turns over on its legs, which, being soft, cannot sup¬ 
port the body, however; but by remaining quiet, the 
creature gains strength, hardness, and courage, and 
the first use it makes of its returning vigour is to 
thrust the old covering outside of its den, or else bury 
it. But when a cast-off suit of armour can be secured 
whole, it is about one-fourth less than the size of the 
lobster which came out of it, and one can hardly 


264 CRUSTACEA , ECHINODERMS, ETC. 

credit that it could have occupied so small a space. 
In about three days the newly attired lobster can go 
about with its mates on equal terms.” 

Among many other long-bodied Crustacea ( Ma - 
croura) which are acclimatised in marine aquaria, 
shrimps and prawns are of course very abundant. 
The former is the stock-food for an enormous num¬ 
ber of fishes and other animals; and the intense 


Fig. 193- 



Prawn (Palcemon serratus). 


stir there is created in a tank containing fishes when 
a supply of fresh shrimps is introduced is quite 
exciting. Both prawns and shrimps are hatched 
from the eggs, like crabs, in what is called the 
“ zoea stage,” in which the five hinder pairs of de- 
capodal legs are wanting, whilst the two pairs of 
foot-jaws are employed as locomotive organs. These 
useful aquarium crustaceans may generally be seen 


SPECIES OF SHRIMPS. 


265 


distributed through all the large tanks alike, but their 
transparent appearance makes them difficult to be 
seen. The usual position of prawns when at rest 
is near the edges of rockwork, over which they glide 
by means of their bristle-like feet. The Crystal 


Fig. 194. 



Common Shrimp (Crangoti vulgaris). 
Fig- 195- 



Palcemon squilla. 


Palace Aquarium is especially rich in Crustacea, both 
long-tailed, as lobsters, shrimps ( Macroura ) ; and 
short-tailed ( Brachyurd), as crabs. The shrimps love 
to burrow and hide in the fine sand at the bottom, 
and to throw a thin cloud of it over them by means 







266 CRUSTACEA , ECHINODERMS , ETC. 


of their feet. When thus hiding, the speckled light 
grey colour of their bodies is admirably adjusted 
to the appearance of the floor. Among other aqua¬ 
rian crustaceans, some of them lower in organisation 
than those we have just mentioned, and others of 
which are more or less nearly related, may be 
mentioned the opossum shrimp (Mysis; the Hip- 
polyte , an animal which assumes a bright green and 


Fig. 196 . 



Hippolyte varians. Banded Shrimp (Crangon fasciatus). 

red colour at will; the banded shrimp (Crangon 
fasciatus') ; and the night-walker (Nika eduiis). The 
banded shrimp is occasionally sold among the oft- 
times miscellaneous mixture which goes by the name 
of “ shrimps the night-walker has derived its name 
from its peculiar nocturnal habits. In addition to 
these may be seen the interesting Gammarus (also 
frequently sold and eaten as a “ cup-shrimp”). No hen 
could exceed in anxiety for her chicks, the maternal 



NIKA AND GAMMARUS. 


2 67 


devotion of this little crustacean for her brood ; which 
repay her for her attention by following her about 

Fig. 198 



Night-walker (Nika edulis). 
Fig. 199. 



batnmarus locusta , and her brood. 


after chicken fashion. Squat lobsters is the name 
rriven to a group of brilliantly coloured Crustacea 




































268 CRUSTACEA, ECHINODERMS , ETC, 


which, in some points, are intermediate between the 
long-bodied lobster family, and the short-bodied crabs. 
They are generally nocturnal in their habits, when 
they are very stirring. By day they lurk beneath 



stones, &c., with their long tails folded up beneath 
them, and in their natural habitats affect deepish 
water. Off the Devonshire and Cornish coasts they 
are not uncommon. 

Of crabs we have of course an abundance. The 





VARIOUS SPECIES OF CRABS. 269 

common shore-crab ( Carcinus mcenas) we have already 
seen is, like the shrimp, regarded as “ live stock” by 
aquarium managers, and generally kept in special 
tanks until required, or provisionally used as a 
scavenger, to clear away any decomposing animal 
matter. The edible crab ( Cancer pagurus ) is too 
valuable to be thus utilised, especially when the 
common, and to us uneatable “ shore crab ” will do 
as well. The spiny spider crab ( Maia squinado) 
grows to a large size, and is as attractive among the 
short-bodied Crustacea as the spiny lobster is among 
the long-bodied. All the spider crabs are nocturnal 
in their habits, and are generally so sluggish that we 
may see miniature forests of zoophytes and sea-weeds 
growing on their carapaces, or shells as they are 
popularly termed. It has been proved by Mr. Lloyd 
and others that one species, at least, is in the habit 
of daintily decking itself with sea-weeds, &c., as had 
been stated, and afterwards controverted. Miss G. 
Stephens has also recorded the fact as occurring in 
the genus Pisa. The body of the last species is co¬ 
vered with tough prickles. Nearly allied to it is the 
true spider crab ( Hyas aranezis), one of the largest of 
British species, if length of limb is to be taken into 
consideration in measurement; these long legs having 
obtained for it the adjectival denomination of “spider 
crab.” One allied British species is the four-horned 
spider crab ( Pisa tetraodon ), whose stout carapace is 
covered, especially along the margin, with strong in- 


270 CRUSTACEA, ECHINODERMS, ETC. 


curved thorns. Inachus Dor settensis , Achceus cranchii, 
and Stenorynchus phalangium are still better entitled 
to the name of “ spider ” crabs, on account of their 
small bodies and extremely long legs. 


Fig. 201 



The Spider Crab (Hyas araneus ). 


In addition to the above, the interesting group of 
“swimming crabs” has been introduced into the Crystal 
Palace and other aquaria, where at least half-a-dozen 
species are to be seen. The principal general are 
Polybius , Portunus , and Portumnus. Their adaptation 
to swimming habits is at once evident on seeing their 
flattened, oar-like hind legs. When swimming they 
usually take to the mid-water. The “ masked crab ” 
is to be found in some of our public acquaria, and is 
undoubtedly one of the most attractive. The male and 
female differ so much in general appearance that they 



CRABS. 


271 


might easily be mistaken for different species* The 
name is derived from a supposed resemblance which 
the carapace bears to the human face. On some 
coasts it is very abundant, and those acquainted with 


Fig. 202. 


Four-horned Spider Crab (Pisa tetraodon), male. 



its habits can easily find it at low water, by slight de¬ 
pressions in the sand, through which its long antennae 
are seen protruding. As a burrowing crab, these long 
antennae are of great service to it, inasmuch as they 
are hollow, and thus form tubes through which the 
water passes to the gills. The male especially has a 
peculiar habit of occasionally sitting upright, like a 
dog in the act of begging, and in this position its very 
long fore-legs assist it materially. The “northern'’ 
scone crab (Lithodes maid) is also a good aquarium 




272 CRUSTACEA , ECHINODERMS, ETC. 



The Masked Crab (Corystes Cassivelaunus), male. 


object, obtained abundantly on the Norway coasts, 
although there was some difficulty in obtaining it at 













Masked crabs. 


m 


first, owing to the superstition of the Norwegian 
sailors, who regard it as “ bewitched.” It is also 
found on the northern shores of Britain. 


Fig. 204. 



Female of Masked Crab ( Corystes Cassivelaunus). 


The Crystal Palace Aquarium possesses living 
specimens of Euryonome aspersa , Hyas coarctus , 
Pirinicla denticulata , Pilumny.s hirtellus , as well as 
the “nut” crabs ( Ebalia ), and the “angled” crabs 

T 







274 CRUSTACEA , ECH/NODERMS, ETC. 

(Gonoplax). The former has the singular habit when 
at rest of simulating the appearance of rounded 
quartz pebbles. In addition to these may also be 
seen the interesting Xantho jiorida and X. rivulosa , as 


Fig. 205. 



Stalked Barnacle [Lefias anatifera). 


well as Dromia vulgaris , or “toad crab,” so called 
from its sluggish appearance. It is covered with a 
kind of pile or hair. The fourth and fifth pairs of legs 
are very short, and close-pressed against the carapace. 






BARNACLES. 


275 


Several species of Mediterranean and American Crus¬ 
tacea may also be seen alive in one or other of these 
tanks of our public aquaria. 

It is only within a few years that the very large and 
widely distributed family of marine animals known as 
n barnacles” ( Cirripedia ) have been proved to belong to 
the same order as crabs and lobsters, and therefore to 
be veritable crustaceans. Darwin’s monograph of these 
interesting creatures has placed them in a new light. 
Unlike the evolution of many animals, which begin 
in a simple way, and gradually pass through em¬ 
bryonic stages to a more complex (as the lobster, for 
example), the barnacles are actually more highly 
organised when they are young, free-swimming, and 
crustacean-like, than when they have reached the adult 
condition. Their life-history is a retrogradation, 
zoologically speaking, in order the better to adapt 
them to the very peculiar habits of 
life which we find them affecting. 

We can group the Cirripedia into 
two natural divisions, stalked and 
sessile, of which the stalked barnacle 
(.Lepas anatifera), and the sessile 
“ acorn” barnacle, we find so un¬ 
comfortably covering seaside rocks, 

are relative examples. The beauti- Sessile Acorn Barnacle 

[Bala nns porcatus ). 

ful plumes or gills protruded from 

the semi-opened calcareous valves of the former, arc 

well known. These constantly sweep the water in 

T 2 


Fig. 206. 



2 76 CRUSTACEA , ECHINODERMS, ETC. 

search of fresh oxygen and food. When the stalked 
species (so called from the flexible muscular tube, 
often of great length, to the free end of which the 
body of the barnacle is attached) have ceased lead¬ 
ing a free-swimming life, they in reality settle down 


Fig. 207. 



Scalpellum vulgare. 


by their heads. The feet then produce the feathery 
gills, and are hereafter employed in sweeping the 
water to and fro, instead of swimming or walking. 
In reality there is not much modification here, for 
if the legs of a lobster be plucked off sharply, there 















BA RNA CLES. 


2 77 


will be found adhering to the point of attachment 
a fringed oval object, which is part of a gill. Even 
in the lobsters, therefore, foot-locomotion is also 
partly subservient to breathing purposes. We have 
several species of both stalked and unstalked bar- 


Fig. 209. 



Goose Tree (Anseres arborei). 

From the ‘ Cosmographia Universalis ’ of Munster 


nacles, of which Scalpelium vulgare (usually found 
attached to the base of those corallines called “ lob¬ 
ster’s horn ”) are abundant among the former, and 
Balanus hameri not unfrequent among the latter. 

The young of Scalpelium pass through very similar 
















27S CRUSTACEA , ECH 1 N 0 DERMS , ^TT. 


changes to those of the larvae of Lepas. Our readers 
will remember the Lepas as that which is usually 
attached in thick clusters to old wreck and drift 
wood These are difficult to keep in aquaria, 
perhaps on account of their open-sea habits. Mr. 
Lloyd, however, managed to keep some alive at the 
Crystal Palace for nearly six months on a floating 


Fig. 210. 

I 



Larva of Lepas Australis in its last stage of development, a. Antennae, 
with sucking disks, b. Carapace, c. Natatory legs. 

bottle, found at Bridport. This species usually goes 
by the common name of the “ goose barnacle, 1 ” from 
a very old notion (prevalent even among naturalists 
two hundred and fifty years ago), that from the shells 
the goose called the “barnacle” was produced. It 
was further believed to be borne by a peculiar kind 
of marine shrub, which was called the “ goose tree ” 









BARNACLES. 


279 


(Anseres arborei). Old Gerarde speaks most deci¬ 
dedly of having witnessed the whole process of deve¬ 
lopment ! The story is much older than his period, 
and was told and illustrated by 
Sebastian Munster, in his ‘ Cosmo- 
graphia Universalis/ as long ago 
as 1572. 

The sessile barnacles appear to 
be more easily acclimatised in 
aquaria than the stalked. The 
latter are usually drifted about at 
sea, and possibly miss this artificial 
mode of aeration when confined in 
a tank. 

The star-fishes, sea-urchins, and 

marine worms, like the Crustacea , 

are capital adjuncts to what we may (enlarged) immedi- 
A J ately after moulting 

call the “ still life ” of an aquarium, the pupal carapace 
.... 1 , -i 1 1 and assuming its natu- 

They fill up as detail, make a good ra i position, a. Ai* 

fore or background, and intensify ^“oultedie^?' 3 ' 017 
the interest always felt in seeing ob¬ 
jects of which we have heard or read alive for the first 
time. The star-fishes and sea-urchins are nearly re¬ 
lated, in spite of their apparent unlikeness, both being 
grouped into an order called Echinodermata , or “ spiny 
skinned.” Both move by means of suckers, which 
are worked by a wonderful hydraulic apparatus from 
within the test or shell. In the sea-urchin the shell is 
made up of at least six hundred pieces, mosaicked 


Fig. 211. 


0 v' 



Young Cirripede 





2 80 CRUSTACEA, E CHINODE RMS, ETC. 

together. Of these, five rows are perforated, and 
through these perforations minute suckers are pro¬ 
truded. They can be elongated when injected with 


Fig. 213. 



Echinus climbing up side of an aquarium by means of its ambulatory 

suckers. 


water, which is strained off from the sea and ad¬ 
mitted to the interior of the sea-urchin through a 
special plate called the “ madreporiform tubercle.” All 
these rows of feet protrude through the needle-like 



























































































SEA-URCHINS AND STAR-FISH. 2Sl 
Fig. 213. 


A. Upper surface of Star-fish. B. Under surface of ditto, showing 

sucking feet. 

double rows of holes, which may be seen in any one 
of the dead tests of the several species of sea-urchin 






































































































282 CRUSTACEA , ECHINODERMS, ETC. 


which frequent our own shores. The spines which 
have earned for this group the popular name of “ Sea- 
urchin,” are attached to minute rounded tubercles, on 
the plan of a “ball-and-socket joint,” and can there¬ 
fore move about in all directions. But the ambulacral 
or sucking-feet can be protruded even beyond them, 
and thus the Echinus, as well as the star-fish, can 


Fig. 214. 



“Five-fingered” Star-fish (Urasier rubens). 


glide horizontally, vertically, or even on surfaces over¬ 
head, with a quiet, ghost-like motion; all the suckers 
being used to warp the body along. In the star-fishes 
(with the exception of the brittle stars, which have no 
“water-vascular system,” as the mechanism of suck¬ 
ing feet is called, but move about by entwining their 
lime-plated, snake-like arms) the sucking feet are 



STAR-FISHES. 


283 


placed in rows underneath, whilst the sea water is ad¬ 
mitted by a filtering plate situated on the upper sur¬ 
face. The Crystal Palace Aquarium has a large 
number of species of this interesting order in the 

Fig. 215. 



living state, among which we may mention Uraster , 
or “ five-fingered star-fish ” ; Solaster, or “ twelve-rayed 
star-fish;” cushion stars ( Goniaster ), “bird’s foot” 
star-fish ( Palmipes ), Cribella , Comatula (a species 
allied to the crinoids, and which is indeed a crinoid 
in its larval state) ; Asterina , &c. Among the brittle- 



284 CRUSTACEA ECHINODERMS, ETC. 


stars (so called from the readiness with which they 
detach their arms when captured), we may there be¬ 
hold Luidia fragilisissima (which has never been 
kept healthily alive before), Ophiocoma , Ophiura , &c. 
The “five-fingered ” star-fish ( Ur aster rubens) is very 
destructive to oysters, and may be seen in aquaria 
devouring these delicious mollusca by insinuating 
its bladder-like stomach between the two shells. 
These, in some mysterious way, soon succumb to the 
star-fish, and open as if the oyster were completely 
paralysed ; so that the soft body is not long before it 
becomes the prey of the persevering star-fish. 

The “ sea-cucumbers ” (. Holothuriadce ), as well as the 
Sipimculidce —a group of marine transitionary worms, 
intermediate in many respects between the annelids 
and some of the Echinodermata —are also represented 
in most of our aquaria. 

The sea worms proper are very numerous. Some 
of them are too rapacious to be kept, except by them¬ 
selves, and do injury to the rest of the inhabitants of 
the tank. Among these is the black Borlase’s worm 
(Nemertes Borlasii ), several yards in length, which 
stretches from one end of the tank to the other, like so 
many foldings of ribbon. The Terebeila is an interest¬ 
ing object, half-way between naked worms and those 
which live in limey tubes of their own secreting. The 
Terebeila simply forms an outer protection by cement¬ 
ing grains of sand together, after the manner of a 
caddis-worm. Serpulce (which may be seen in abun- 


SEA WORMS. 


285 


dance on the backs of old oyster shells, &c.) secrete 
a calcareous tube, as compact as the valve of a 
mollusc. The crimson plumes are protruded from 
the upper part, and these sweep the water for fresh 

Fig. 216. Fig. 217. 



7\ 

Tube of Terebella. 


Sabella unispira. 


air. In colour they are very contrasted with the 
larger and still more feather-like gills of the Sabella 
—a large marine worm, to be seen in marine tanks 
burrowing in sand, or affixed to stones—which are 
generally of a dull grey, although they are sometimes 




















286 CRUSTACEA, ECHINODERMS , ETC. 


of a bright colour. This marine worm also constructs 
its long and elegantly convoluted tube by means of 
cemented grains of sand. 

In addition to these our public aquaria have Sabcl- 


Fig. 218. 



“Sea-mouse” (Aphrodita aculeata). a. Under surface, b. Side view. 

laria , Eunice , Aphrodita , Polynoe , Nereis , Pontobdella , 
Arenicola (or “lob-worm ”), Protula , Spiv or bis, Phlly- 
doce (a worm of attractive appearance), Eunice\ 
Pectinavia , Othonia , &c. These interesting creatures 






SEA WORMS. 


287 


have been made a speciality at the Crystal Palace, 
where the largest number of varieties may be seen 
alive. Of all these marine worms, however, certainly 
none is so attractive and so much sought after as the 
“sea-mous q” (Aphrodita aculeata). Its metallic lustre 
of green, blue, and yellow hairs, shining like those of 
the peacock’s tail, would make it attractive by what¬ 
soever name it might be called. Few people can 


Fig. 219. 



Nereis. 


believe that this beautiful and not uncommon crea¬ 
ture is a marine worm. Its back is covered with 
plates, underneath which are the breathing organs 
or gills. The plates are covered with the iridescent 
bristles, which, although beautiful even when the 
Aphrodita is cast up as a dead object at high 
water, are exceedingly lovely when it is seen alive 




288 CRUSTACEA , ECHINODERMS, ETC. 


and healthy in an aquarium. There can be no 
wonder, therefore, that it is sought after, and con¬ 
sequently exhibited in our public aquaria. Others 
of the non-tubed worms, the Nereis , for example, 
although not so brilliantly coloured, are very graceful 
and pretty marine creatures. The habits of some of 
the prettiest, however, belie their lovely appearance; 
for they are not unfrequently those of the well-clad 
stage ruffian who struts about in garments which 
have been obtained by means of murder and robbery. 
Not a few of the “ errant,” or wandering worms, live 
by stealthily preying upon objects actually more 
highly organised than themselves. 


SEA-ANEMONES. 


289 


CHAPTER XVI. 

SEA-ANEMONES AND OTHER ZOOPHYTES, ETC., 

OF MARINE AQUARIA. 

Even before the days of large public aquaria, Gosse, 
Lankester, and others had taught us the ease with 
which those charming, flower-like objects called u sea- 
anemones ” could be kept alive in vessels of sea water. 
No flowers in full bloom exceed them in colour or 
graceful shape, whilst in them there is superadded the 
extra interest which life gives to any object. These 
sea-anemones ( Actinia ) have been studied and ob¬ 
served more than any other group of marine animals. 
They are easy to keep alive, with certain necessary 
precautions, but require some little feeding. So 
flower-like are they that even insects are occasion¬ 
ally deceived by their floral appearance. Sir John 
Lubbock and others have recently shown how won¬ 
derfully co-related flowers and insects are ; and if 
it had been a less trustworthy observer than the 
late Jonathan Couch who related the following, it 
would have been difficult to believe that an insect 
so intelligent as a bee could make so gross a mis¬ 
take as to take a sea-anemone for an open flower! 
Mr. Couch states that he saw an expanded “ crass ” 


2 QO SEA-ANEMONES, ZOOPHYTES , ETC. 


or “dahlia” wartlet anemone (Tealia crassicornis ), 
which was just covered by a film of sea water in a 
rock-pool. It looked very attractive, and whilst he 
was admiring its beauty a bee buzzed straight into 
the embraces of the “ crass,” mistaking the tentacles 
for petals, and paying for the error with its life, for 
the remorseless fingers clutched it in their grasp and 
transferred it to the ready stomach ! 


Fig. 220. 



The Dahlia Wartlet (Tealia crassicornis ). 


The bright colours and elegant shapes of sea-ane- 
moncs have caused them to be much sought after, 
both by amateur aquarium-keepers and the managers 
of our public institutions. About thirty species of 
them and their allies may be seen living in the tanks 
of the Crystal Palace, where they are usually fed on 


















SEA-ANEMONES. 


291 


a diet of chopped mussels, conveyed to them by 
wooden forceps. In the sea they are thankful for 


Fig. 221. 



any organic waif or stray that may come within their 
reach. In the deeper tanks, where certain sea-ane¬ 
mones are placed, when live shrimps are turned into 

U 2 



















































































292 SEA-ANEMONES , ZOOPHYTES , .E7T. 

the water the anemones occasionally catch them. 
Some species can slowly move from one place to 
another by means of the base of the column, after the 
manner of a snail crawling. Perhaps the most noble 
looking of all this group of animals is the plumose 
anemone (Actinoloba diantkus), whose crown of fea¬ 
thered tentacless entitle it to the name of “ sea- 
pink.” Its base is more expanded than is usual 
with other sea-anemones. The species called the 


Fig. 222. 



The Orange-disked Anemone (Sagarlia venusta). 


‘‘orange-disk anemone” (Sagartia venusta ) is named 
from its prevailing colour ; the tentacles, how¬ 
ever, being a pure white. The genus Sagartia 
was so named by Gosse on account of their 
possessing peculiar kinds of thread-darts, stored in 
“ nettling cells,” which they can throw out, so as to 
benumb and overcome their prey. They are the 
most active of all the sea-anemones, and bear the 



SEA-A NEMO NES. 


293 


most variegated colours, so that some species are 
indicated by names of colour. Thus we have the 
snowy anemone ( Sagartia nivea), the rosy anemone 
(Sagartia rosea), &c. Their habits of life, also, 
seem more various than those of any other genus. 
One is called the “ cave-anemone ” ( Sagartia troglo¬ 
dytes ), from its habit of burrowing. Another well- 

Fig. 223. 



The Daisy Anemone (Sagartia bellis). 


known species of Sagartia is called the “ daisy ”; 
whilst a very interesting species has formed some 
sort of an alliance with hermit crabs, so that it is 
usually found covering the shell in which one of these 
crustaceans has taken up its abode, and is therefore 
called the parasitic anemone {Sagartia parasitica). 
This is not the only sea-anemone which has contracted 





294 SEA-ANEMONES , ZOOPHYTES , ETC. 

such a singular friendship. We have "a pink-spotted 
one called the “cloaklet” (Adatnsia palliata ), so-called 
because it has no “column,” and therefore spreads 

itself over the shell like a 
mantle. The attachment of 
these anemones for the her¬ 
mit crabs is mutual, insomuch 
that when the latter change 
their shells for a larger, just 
before moulting, they will re¬ 
move their zoophytal com¬ 
panions to their new abodes. 
Van Beneden has termed this 
strange association “ commen¬ 
salism,” or “ messmateship.” 
Some of our public aquaria 
exhibit these species of sea-anemones in the position 
we have just described. 

The commonest anemone is that known as the 
“beadlet” (Actinia mesembryanthemuni), whose spe¬ 
cific name is vulgarly shortened to “ mes,” as that 
of the “ dahlia wartlet ” is to “ crass.” It is a pretty 
creature, and cannot be too common; for its red ten¬ 
tacles, with their ring of turquoise-like spots, are ex¬ 
quisitely flower-like. It is also very hardy and long- 
lived, one specimen in Scotland having attained the 
authenticated age of more than forty years. All the 
sea-anemones, however, seem to be very sensitive at 
the base or foot of the column. If this be hurt they 


Fig. 224. 



Parasitic Anemone (Sagartia 
parasitica). 





SEA-ANEMONES. 


295 


die or are sickly, so that the best way is either to 
peel them gently off the rock they are attached to, 
or else to chip off the rock fragment to which a 
specimen is adhering, so as to bring both away. 


The Beadlet. 

(A ctinia mesembryanthemum). 


Fig. 226. 



The Opelet (Anthea cereus). 


Corals differ from sea-anemones in having an in¬ 
terior hard skeleton, formed of lime. This is part 
and parcel of the animal, just as our bones are of our 
own bodies. If our readers can imagine the radiated 
walls seen in a cross-section of the interior of the 
body of a common sea-anemone to have the power of 
secreting lime, they will understand how the radiating 
septa of corals are formed. When a coral zoophyte 
is dead, the anemone-like flesh and tentacles which 
covered it decompose, and thus there is left behind 
the pretty, hard, whitish body we call “ coral.” The 
red coral of commerce, so valued in jewellery, is a 
tinted calcareous skeleton secreted by another group 
of animals (not the true coral animal), which belongs 
to the same class as the “sea-fans” ( Gorgonidcv). In 



Fig. 225. 







29 6 SEA-ANEMONES , ZOOPHYTES , iSTC. 




Caryophyllia. 

phyllia and Balanophyllia. They may be seen alive 
in nearly all our aquaria, and should be examined 
in order to gain a clear idea of what a coral animal 
really is like. It is very difficult to convey the correct 
idea—people have called them “ insects,” and ima- 


the compound corals, which are chiefly reef-building, 
the individual zoophytes are usually smaller, as in the 
Millepores. Two of our British genera are Caryo - 

Fig. 227. 


Balanophyllia regia. 


Fig. 228. 




















CORALS, ETC. 


297 


gined they built up the 
hard limey coral as bees 
do their combs; whereas 
we have seen it is really 
part of themselves, covered 
over with flesh (except the 
base in very old specimens) 
when the animals are alive. 
Balanophyllia verrucosa is a 
species most generally seen. 
It is of a bright orange 
colour, and abounds in the 
Mediterranean. Several 
living Italian species are 
exhibited at the Crystal 
Palace Aquarium. 

The dead man’s fingers 
(A Icyonium digitatum) is an 
object well known to fisher¬ 
men, both by this name and 
that of “ cow’s paps,” &c. 
It is dredged up from 
deepish water, although 
frequently found stranded 
between tides. It is usually 
attached by its base, the 
body swelling upwards, and 
covered with papillae when 
taken out of the water. 
The general body colour 


Fig. 229. 



Dead Man’s Fingers {AIcyonium digitatum). 



298 SEA-ANEMONES, ZOOPHYTES , ETC . 


varies from yellowish-white to orange-red. Each of 
the little papillae, when the Alcyonium is alive, ex¬ 
pands into a lovely flower-like animal, so that the 
fleshy-looking mass called dead man’s fingers is in 
reality a colony of zoophytes. The flesh is braced by 
the distribution through it of a number of spicules of 
lime. At the Crystal Palace, Brighton, and else¬ 
where, these objects are kept alive, and the action of 
the fringed petal-like tentacles of the zoophytes may 
be witnessed through a magnifying glass. Alcyonium 
is one of the sea-fans ( Gorgonidce ), the dried, horny 
skeletons of which may often be seen in mariners’ 
houses, or in museums. They usually possess a dark 
horny axis covered with a red, orange, or pinkish 
skin, when dried. These objects are also colonies of 
zoophytes, of whose hard horny skeleton we have 
been speaking. When alive this skeleton is covered 
with flesh, and out of the latter there spring buds, 
just as the bark covers a tree, and allows buds to 
burst through it. We give the figure of a well-known 
form called Isis hippuris , in which the relation of the 
skeleton to the external flesh and zoophytes is at 
once seen. Isis is found on the east coast of Scot¬ 
land, and the Orkney Islands. 

We have several species of British gorgonias, of 
which perhaps Gorgonia verrucosa , and G. flabeilum 
are the largest and handsomest. These have been 
kept alive at the Crystal Palace Aquarium for a short 
time, but there is a difficulty in knowing how to feed 


SEA-FANS. 


299 


them, so that they soon die. In the “ fan ” gorgonia 
( G.flabelium ) the branches run into each other, so as to 


Fig. 230. 



Isis hippuris X 5 (vertical section), showing flesh, with zoophytes 
investing internal horny axis, a, external appearance. 

unite. In Fig. 232, we give a slightly magnified illus¬ 
tration of part of one of the branches. The circular 
pits, one in the common flesh ( Ccenosarc ) which invests 
the skeleton, and one occupied by the individual 
polypes. All the British species of this interesting 
order are exceedingly pretty; although not to be 
compared with the gorgeous appearance of the sea^ 















300 SEA-ANEMONES , ZOOPHYTES, ETC. 


fans of tropical seas—so graphically described by 
Schleiden. We should be glad to see more of them 


Fig. 231. 

. - ( 1 ^ ^ 0 ^ f / 




'^dOO 

'WSS’r 1 


’Cy 



The Common Sea-fan (Gorgonia flabellum). 

kept in our public aquaria, as the dried specimens 
are very common and well-known ; although most 






SEA-FANS. 


301 


people, even when generally well educated, know 
little of what they are. If shown in a tank in the 


Fig. 232. 



Small portion of Gorgonia flabellum , showing pits in coenosarc, 

occupied by Polypes. 

living state, this ignorance would vanish at their 
first sight. In Gorgonia verticillaria the polypes are 
arranged around the axis like the leaves of such a 
verticellate plant as the common “ goose grass ” or 
“ cleavers.” The species called pinnata, is not very 
fan-like in shape, although there needs little effort 
to see that it belongs to the sea-fans. We have 
referred particularly to our British species because 
we think it would be easier to domesticate them in 
aquaria than foreign species. Some of them are not 




302 SEA-ANEMONES , ZOOPHYTES , 


rare off the southern coasts of England, and may 
easily be obtained alive. 

The smaller zoophytes are too inconspicuous to be 
kept in tanks for public exhibition, although many 
naturalists keep them alive for purposes of research. 


Fig. 233. 



Gorgonia verticillaria. 

No other group of marine animals is so interesting, 
especially since it has been discovered that the 
minute Campanularians give rise to large jelly-fish¬ 
like progeny. Indeed, many of the so-called me- 
dusoid jelly-fishes are but the larval conditions of 







304 SEA-ANEMONES , ZOOPHYTES , 


hydroid zoophytes. Few of these campanularians 
are more than half an inch in length, and are rarely 
noticed by any but naturalists. And yet they are 

Fig. 235. 



Diagrammatic sketch of Campanularia dichotoma , showing common 
flesh ( m), cilia of each zoophyte [d), body of zoophyte (g) , &c. 

covered with the minute cups of living zoophytes 
(Fig. 235, d, g, h, &c.). The “oaten-pipe” coralline 
{Tubularia indivisa), with its coronal of scarlet 














CORALLINES. 


305 


tentacles, waving from out the horny “ pipes,” is 
a well-known object, and this may be seen at the 
Crystal Palace, together with the “ lobster’s horn ” 

Fig. 236. 



coralline (Antennularia antenninci), and the true sea- 
fir (Seriularia abietina, Fig. 183), all of them hydroid 
zoophytes. It is difficult to preserve jelly fishes, 

X 


30 6 SEA-ANEMONES, ZOOPHYTES , ETC . 


although Cydippe has been kept alive a little time, 
and we have seen the larval Medusa at Brighton and 
the Crystal Palace, not bigger than a pin’s head, 
which had been hatched in the tanks. The pretty 
little Hydra-tuba may also be searched for and found 


Fig. 237. 



Hydra-tuba, in various stages of segmentation. 


in these places ; and in them, again, we have evi¬ 
dence of how “jelly fishes” can be formed from an 
object less than half an inch in height, by the “seg¬ 
mentation,” or splitting up into free parts, of saucer¬ 
like objects, which turn over into umbrella-like disks, 
and then swim away, as utterly unlike their parents 
as any two animals can well be. 

Sponges will always be difficult objects to keep 
alive under artificial conditions, although we have 
seen that the most delicate of all of them, the fresh¬ 
water sponge (Spongilla fiuviatilis) has succumbed to 
the will and care of man in this respect. Several of 
our commonest British sponges are kept alive at 
Brighton, Manchester, and especially at Sydenham, 


MARINE SPONGES. ' 


3°7 


where they grow so well that they form masses as 
big as a man’s head. But some of them are not 
attractive-looking creatures ; and, indeed, few people 
would imagine them to be animals at all. The 
spongy object which we know as sponge, is only 
the inner skeleton ; just as coral is of another class 
of marine animals when alive. This substance is 
covered all over with a transparent gelatinous flesh, 
called sarcode , which lines every pore and every aper¬ 
ture. In and out of these currents of sea water per¬ 
petually flow, induced by the action of the eyelash-like 
processes {cilia) with which the surface of the flesh 
lining such hollows is covered. Among them we have 
the “ crumb-of-bread ” sponge {Halichondria panicea } 
Fig. 238), the Chalina ocalata, Fig. 239 (largest of our 
British sponges), the Leucosalenia , Tethea , Grantia , 
Hymeniacidon , Cliona — the latter is really a boring 
sponge, and burrows the holes we may see covering the 
surfaces of old oyster-shells. Some of these sponges 
are of a brilliant yellow or crimson colour, and mat 
the surfaces of rockwork, &c., having been introduced 
into the sea water as “ gemmules,” and developed by 
circumstances into their present attractive and useful 
conditions. 

No doubt the marine aquarium might be converted 
into a nursery for microscopic objects as well as the 
fresh water. There is no end to the variety of the 
lower forms of life inhabiting the sea. They are 
the oldest of all the animal kingdom, having been in 

x 2 


30 S SEA-ANEMONES , ZOOPHYTES , ETC. 


existence since perhaps before the distant Laurentian 
epoch of which geology speaks. They have expe¬ 
rienced all the changes which we know the ocean 
beds must have experienced—have repeatedly wit¬ 
nessed the conversion of continent into sea, and 


Fig. 238. 



ocean floor into dry land and even mountain chain. 
The mineral remains of some of the ancestors of 
living forms have taken an active part in the building 
up of rock masses of every geological period. We 
cannot wonder, therefore, that the number of species 
of these early and unpretending forms of life should 


BRITISH SPONGES. 


309 




310 SEA-ANEMONES , ZOOPHYTES , TT/T. 


be so great, or that they should enjoy so cosmo¬ 
politan a distribution. There is no reason why more 
naturalists should not cultivate the humblest as well 
as the most highly-developed types of marine life, 
and keep living marine diatoms, foraminiferae, nocti- 
lucae, and sponges. Our rock-pools support them, 
and it is a sad proof of how little we yet know of 
the natural conditions of such little spots as these, 
if we cannot keep them artificially alive also. 

That aquaria are still in the infancy of their deve¬ 
lopment we do not doubt, any more than that they 
will administer to the growing love of animated na¬ 
ture which is the especial feature of the intellectual 
culture of our century. Here will have to be fought 
out and hunted down many of the embryological 
questions to which deep philosophical inquiry is now 
attaching such great importance. And, whilst aquaria 
may in this manner be useful to true science, they 
will not be less so to unscientific people, in revealing 
to them at a glance the shapes, habits, and natures 
of creatures they had never heard of before, so as 
thus to form a practical education all the more 
valuable because those who learn are for the time 
unaware of its importance. 


( 3i i ) 


INDEX. 



PAGE 


PAGE 

Acanthias vulgaris 

172, 

l8l 

Aspect for aquarium 

.. 40 

Acipenser rutheorus 

• • 

217 

Aspidophorus Europasus 

202 

Acipenser sturio .. 


216 

Asterina. 

.. 283 

Acorus calamus 


93 



Actinia. 


289 

Balanophyllia .. 


Actinia mesembryanthemum 

294 

Balanus hameri 


Actinoloba dianthus 

• • 

291 

Balanus porcatus .. 

.. 275 

Adamsia palliata .. 


294 

Ballan wrasse. 

.. 194 

Aeration of aquaria 

M T 

i 

162 

Barnacles . 


Air supply to Dublin Aqua- 


Batis vulgaris 


rium . 


15 

Bell-glass . 

.. 38 

Alcyonium digitatum .. 

• 0 

297 

Belone vulgaris 


Alisma plantago .. 


76 

Bleak . 

.. 65 

Alligators . 


177 

Blennius ocellatus .. 


Amoeba. 


124 

Blennius pholis 

.. 188 

Amphioxus lanceolatus 

9 0 

179 

Botryllus. 

.. 251 

Anacharis . 


58 

Brighton Aquarium 

19, 165 

Ancient fish-ponds 

0 9 

5 

Buccinum undatum 

.. 236 

Angel fish . 

I84, 

197 

Butomus umbellatus 

77 

Annarhicas lupus .. 


187 

Bythinia. 

.. 103 

Annelids. 


254 



Anodonta cygnea .. 


103 

Caddis-worms .. 

104, 109 

Antennularia antennina 

• . 

305 

Calithamnion 

•• 143 

Anthea cereus 


295 

Callionymus lyra .. 


Aphrodita . 


287 

Callitriche . 

•• 55 

Aquatic plants 


72 

Callitriche verna .. 

90. 92 

Ax*achnida; . 


112 

Campanularia dichotoma 

•• 304 

Argyoneta aquatica 

• • 

hi 

Cancer pagurus 


Artificial sea-water 

16, 

i 57 

Cantharus griseus .. 

.. 215 

Ascidia intestinalis 

0 0 

246 

Carcinus moenas .. 


Ascidia vitrea 


246 

Cardium echinatum 

.. 242 












































312 


INDEX. 





PAGE 



PAGE 

Cardium edule .. .. 

• • 

242 

Cyprina moneta .. .. 


242 

Carp . 


64 

Cyprinus. 

• • 

62 

Carp, introduction of .. 

• • 

7 

Cyprinus alburnus 

• 9 

65 

Caryophyllia. 


296 

Cyprinus carpio 


64 

Cat-fish. 


187 

Cyprinus gibelio .. 


64 

Cement. 


40 

Cyprinus rutilus 


66 

Cephalopoda. 


228 




Ceratophyllum demersum 

• • 

93 

Daphne pulex .. 


137 

Chalina oculata 


309 

Daubeny, experiments of 

• • 

12 

Charcoal, its use .. 


45 

Delesseria sanguinea 

• • 

144 

Cheap aquarium .. 


37 

Desmids. 


114 

Chelonia imbricata 

• • 

177 

Devil fish . 


228 

Chiton fascicularis 

• • 

236 

Diatoms. 


114 

Chondrus crispus .. 

145, 148 

Dohrn’s aquarium .. 


20 

Cirripedia . 


275 

Donax . 


245 

Cladophora. 


141 

Doris . 


238 

Cliona . 


307 

Dragon-flies. 


105 

Closterium striolatum .. 

• • 

116 

Dromia vulgaris .. 


274 

Cobitis barbatula .. 


60 

Duckweed . 


43 

Cocconeis insida .. 


120 

Dyticus. 


105 

Cocconeis major .. 


120 

Dyticus marginalis 

• • 

106 

Codium tomentosum 

• • 

146 




Colymbetes. 


108 

Echinoderms 

254 * 

279 

Comatula . 


283 

Echinus. 


282 

Conger vulgaris 


227 

Eggs of newt. 


55 

Construction of fresh-water 


Eledone cirrhosa .. 

• • 

234 

aquarium. 


36 

Ephemerae . 

• • 

hi 

“Convalescent” glass .. 

• • 

48 

Epistylis. 


130 

Corallina officinalis 

• • 

146 

Esox lucius . 


67 

Corystes Cassivelaunus 

• • 

272 

Euastrum oblongum 


115 

Cosmarium margaritiferum 

• • 

116 

Euryonome aspersa 


273 

Cottus gobio. 


60 

Evaporation. 


155 

Crangon fasciatus .. 


266 

Extemporised fountain .. 


34 

Crangon vulgaris .. 


264 




Crenilabrus melops 

• • 

195 

Failure of aquaria .. 

• • 

28 

Cribella. 


283 

Feeding fish. 

• • 

47 

Crustacea . 


254 

Fish in museums .. 

♦ • 

15 

Crystal Palace Aquarium 


161 

Fish-ponds, ancient 

• • 

5 

Cyclops. 


*35 , 

Fish-ponds, necessity for 

• • 

6 

Cyclopterus lurnpus 

• • 

199 

Fissurella Graeca .. 


235 

Cynthia. 


247 

Flat-fish. 


222 

























































INDEX. 3 1 3 



PAGE 



PAGE 

Flustra truncata .. .. 


History of aquaria . . 


I 

Food for fish . 


Holothuriadae 


284 

Frogs, edible. 

7 

Homarus vulgaris .. 


258 

Fucus canaliculatus 

145 , 149 

How to make cheap aquar 

ta 

37 

Fungoid growth on fish 

71 

Hurwood’s contrivance 

• • 

i6 3 



Hyalotheca dissiliens .. 

■ 0 

US 

Gadus luscus .. 


Hyas araneus. 


269 

Gadus merlangus .. 


Hyas coarctus 


273 

Gadus morrhua 


Hydra-tuba. 


306 

Gadus oegelfinus .. 

.. 213 

Hydra viridis . 


125 

Gadus pollachius .. 

.. 211 

Hydrocharis morsus-ranae 

• • 

85 

Galathea squamifera 

.. 268 

Hydrophilus piceus 

• • 

127 

Galeus canis . 





Gammarus . 


Illumination of tanks 

BY 


Gasterosteus semi-armatus 

60 

NIGHT . 


4 

Gasterosteus spinachia .. 

.. 201 

Insects, fresh-water 


97 

Gasterosteus trachurus .. 

60 

Interchange of fish 


6 

Gobio fluviatilis 


Irish moss . 


148 

Gobius minutus 

.. 191 

Isthmia enervis 


1 19 

Gobius niger . 





Goldfish . 

• • 6, 58 

Kent on herring culture 

3 

Gorgonia flabellum 

.. 298 




Gorgonia pinnata .. 

•• 30 3 

Labrus maculatus .. 


192 

Gorgonia verrucosa 

.. 298 

Labrus mixtus 


193 

Gosse’s sea water .. 


Labrax lupus. 


207 

Grampus griseus .. 


Lemna. 

43, 88 

Growth of salmon .. 

4 

Lepas anatifera 


274 

Growth of salmon-trout 

4 

Lepidosteus osseus 


69 

Gurnards . 


Leuciscus rutilus .. 


66 



Licmophora flabellata .. 


121 

Halichondria panicea 

•• 307 

Light, effect of 


30 

Halidrys siliquosa .. 

146, 150 

Light in aquaria .. 


154 

Haliotis tuberculata 

15 °, 237 

Limnea auricularia 


99 

Hottonia palustris .. 

.. 81 

Limnea pereger 


100 

Hermit crabs. 

.. 254 

Limnea stagnalis .. 


99 

Herring culture 

3 , 173 

Limnephilus. 


IIO 

Hippocampus 

.. 217 

Limpet. 


151 

Hippocampus breviostris 

.. 221 

Lissotriton palmipes 


57 

Hippocampus ramulosus 

.. 221 

Lithodes maia 


271 

I lippolyte varians .. 


Lloyd on herring culture 


3 

Hippuris . 


Lobster. 


256 




























































INDEX. 


314 


PAGE 


Loligo vulgaris . 233 

Lophius piscatorius .. .. 197 

Lophopus crystallina .. .. 133 

Luidia fragilissima .. .. 284 

Mactras . 245 

Maia squinado . 269 

Manchester Aquarium .. 21, 268 

Marine aquaria, commence¬ 
ment of . 14 

Marine aquarium for rooms.. 139 

Masked crab. 272 

Melicerta . 127 

Membranipora pilosa .. .. 249 

Mentha aquatica. 80 

Menyanthes trifoliata .. .. 83 

Merlangus carbonarius .. .. 213 

Mici'asterias. 116 

Microscope. 113 

Millepores . 296 

Modiola. 245 

Modiolus . 245 

Mollusca, fresh-water .. .. 97 

Motella mustela . 213 

Motella tricirrata. 213 

Moulins’ aquarium .. .. 11 

Mugil capito. 214 


Mussel. 239 


Mustulus vulgaris. 180 ! 

Mya arenaria. 244 

Mya truncata. 244 

Myriophyllum spicatum .. 89 

Mysis chameleon. 222 

Mysis of lobster . 260 

Mytilus edulis . 239 

Naples Aquarium .. .. 20 

Navicula didyma. 118 

Nemertes Borlasii. 284 

Nereis . 287 

Newts . 52 

Nika edulis. 266 


Nitophyllium.. 

PAGE 

Notonecta . 

. 108 

Nudibranchiata 

• 237 

Nuphar lutea. 


Nympha alba. 

. 76 

Octopus vulgaris 

. 229 

Ophiocoma neglecta 

. 283 

Opossum shrimp .. 

. 222 

Ormer shell. 

• I 5 i 

Otaria . 

• 177 

Ova of codfish 


Over-stocked aquaria .. 

. 28 

Oysters. 


Oyster spat . 


Pal/emon serratus .. 

264 

Pakemon squilla .. 


I’alinurus quadricornis .. 

• 256 

Paludina vivipara .. 

102 

Pagurus Bernhardus 

• 254 

Patella vulgaris 

• IS* 

Pecten . 

• 243 

Penekese Island Aquarium 

. 21 

Perea fluviatilis minor .. 

, 62 

Pholas . 

• 243 

Phoxinus lsevis 

. 62 

Phryganeidse. 

no 

Phyllosoma . 

4, 258 

Picked dog-fish 


Pike . 

67 

Pilchards . 


Pilumnus hirtellus 

• 273 

Pinna pectinata 

• 245 

Pinnularia major .. 

. 118 

Pirimela denticulata 

• 273 

Pisa tetraodon 

. 269 

Pisidium. 

. 103 

“ Pixy purses ” 

. 182 

Planorbis corneus .. .. 


Plants for aquarium 

• 43 

Platessa limanda .. 






























































INDEX. 


315 


PAGE 



PAGH 

Pleuronectes plesus 

224 

Salaster .. 

• • 

283 

Pleurosigma formosum .. 

Il8 

Salia vulgaris.. 


224 

Plocamium plumosum .. 

I44 

Saxicava. 


243 

Plumatella repens. 

134 

Scallop. 

• • 

243 

Polygonum amphibium 

83 

Scalpellum vulgare 

# , 

276 

Polynoe. 

286 

Scyllium canicula .. 

i 73 > 

182 

Pontobdella. 

286 

Scyllium stellare .. 


183 

Pope-fish . 

62 

Sea-lions. 


177 

Porpoises . 

I76 

Sea-mat. 


248 

Potamogeton natans 

91 

Sea-water . 

• • 

156 

Prawn . 

264 

Sea-weeds . 

• • 

145 

Principles of the aquarium .. 

25 

Self-acting air-can.. 

• • 

159 

Protopterus annectens .. 

179 

Sepia officinalis 

* • 

231 

Protula. 

286 

Sepiola Rondeletii 

• • 

233 

Public aquaria . 

l6l 

Sepiostaire . 

• • 

232 



Serpulae. 


284 

Rata batis. 

186 

Sertularians. 


249 

Raia clavata. 

185 

Shrimp, common .. 


264 

Raia lintoa . 

186 

Silurus. 


68 

Raia maculata . 

I85 

Sipunculidae. 


284 

Rainbow wrasse . 

I96 

Sloped-back tanks.. 


152 

Raniceps trifurcatus 

227 

Small marine tanks 

• • 

140 

Ranunculus aquatilis 

84 

Small-spotted dog-fish .. 

• • 

173 

Red mullet . 

5 

Soil of bottom of tanks 

• • 

45 

Relation between plants and 


Southport Aquarium .. 

22, 

169 

fish . 

10 

Sparganium ramosum .. 

• • 

93 

Removing dust from water .. 

35 

Specific gravity beads .. 

• • 

157 

Rhina squatina . 

184 

Sphaerium lacustre 

• • 

103 

Rhodymenia palmata .. 

i 47 

Spider crabs. 


270 

Rhombus maximus 

224 

Spongilla fluviatilis 

123, 306 

Rockwork . 

41 

Star-fish. 

• • 

282 

Royal Commission of 1865 .. 

2 , 3 

Stauroneis . 


119 

Rotifers. 

127 

Stephanoceros eichornii 

• • 

129 

Rotifer vulgaris . 

131 

Stickleback. 


59 



“ Stock ” glass 

• • 

38 

Sabella . 

141 

Stratiotes aloides .. 


85 

Sabella unispira . 

285 ! 

Syngnathus acus .. 


218 

Sagartia bellis . 

293 ! 

Syngnathus anguineus .. 

» • 

220 

Sagartia parasitica 

293 I 

Syngnathus aequoreus .. 

» • 

219 

Sagartia venusta. 

292 

Syngnathus typhle 

• • 

218 

Sagittaria sagittifolia .. 

76 

Syphon circulation .. 

• • 

153 


















































INDEX . 


316 


Tealia crassicornis 

PAGE 

.. 29O 

Tectibranchiata 

.. 238 

Temperature of aquaria 

•• 154 

Temperature of water .. 

•• 31 

Terebella . 

.. 141 

Teredo. 


Trachinus draco .. 


Trachinus vipera .. 


Trap a natans. 

.. 88 

Trigla gurnardus .. 


Trigla lineata 


Trigla lyra . 

.. 205 

Triton Bibronii 

•• 57 

Trophon antiquum 

.. 236 

Truncata. 

.. 247 

Tubularia indivisa.. 

.. 304 

Turtle . 

.. 177 

Ulva latissima .. 

.. 141 

Unio . 

.. 103 

Uraster rubens 


Utricularis vulgaris .. 

.. 87 


PAGH 


Vallisneria spiralis .. 74 

Venus . 245 

Veronica becca-bunga .. .. 81 

Villarsia nymphaeoides .. .. 88 

Ward’s experiments .. 13 

Warington’s ditto. 14 

Water flea . 137 

Water never changed .. .. 11 

Water violet. 81 

Westminister Aquarium .. 167 

Wrasse. 192 

XANTHO FLORIDA .. .. 274 

Xantho rivulosa . 274 

Xylophaga . 245 

Yarmouth Aquarium .. 167 

Zeus faber. 227 

Zoarces viviparus. 189 

Zoological Gardens Aquarium 15 
Zostera marina . 146 











































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