62 
THE NEW YORK AQUARIUM JOURNAL. 
THE AQUARIUM. 
• PART H.-ITS FORMATION AND MANAGEMENT. 
We will imagine our aquarium healthily es¬ 
tablished in its vegetation. A crystal globe or 
tank of bright clear water, with plants of the 
pretty long-leaved valisneria, chara, and per¬ 
haps a water ranunculus floating at the top, all 
in their healthy growth giving off bubbles of 
pure oxygen when exposed to the light. At the 
bottom of the tank is a bed of clean river-sand, 
with bits of rock or stones lying about, and 
forming tiny caves or nooks for the retirement of 
any of the expected tenants, of the pool. It has 
required perhaps a fortnight of patient waiting to 
accomplish this condition of things, and careful 
attention in removing every dead or decaying bit 
of vegetation. The tank has been shaded from 
too hot a sun, and exposed to the bright light 
of a warm aspect only occasionally. Were it 
left in a window with sunlight constantly upon 
it, the green vegetable matter called confervae 
would increase and grow so rapidly as to destroy 
the other plants, and forming a green shiny film 
all over the light side of the glass, would obscure 
it entirely. This green film must be daily cleared 
away and the sides of the glass polished. A bit 
of clean sponge tied on to the end of a stick 
answers this purpose well, and if used daily is 
sufficient to keep the glass clear; but if the con¬ 
fervae be neglected, and allowed to establish it¬ 
self, scrubbing will hardly remove it from the 
glass. Almost the first inhabitant that is tried in 
a fresh-water aquarium is a stickleback; he is so 
easily caught, and is the first game of the youth¬ 
ful British angler. A bit of meat at the end of 
a piece of string entices him, and having once 
seized it he neve? lets go till he is dragged out 
of the water and opens his mouth to gasp for 
breath. He very soon accommodates .himself 
.to ..new ...quarts 
once, allowing no intruders, and usually com¬ 
mencing his despotic reign in the aquarium by 
attacking all rivals. It is best not to attempt to 
establish an aquatic ‘ happy family ’ rashly. The 
mild and pleasant little gold and silver fish live 
peacefully with their neighbors; but the trucu¬ 
lent stickleback is a fish to be wary of in the 
way of introduction. Let him have a habitation 
to himself, with one or two of his own species, 
and he is delightful to watch arid beautiful to 
behold. He will repay you for his disposition. 
He has all the ways of other fish and many more 
besides. He. and his family are found both in 
fresh water and in sale. It is almost a matter of 
indifference to them in which they live. In 
Yarrell’s British Fishes we find seven distinct 
sorts of sticklebacks described, according to their 
peculiarities, number of fins, &c., and in each 
case it is mentioned that they are found ‘ indis¬ 
criminately in salt or fresh water,' in every river, 
brook, lake, and all around our coast from Land’s 
End to the Orkneys. 
It is the male fish that is the pugnacious one 
of his tribe. We have no Amazons among fishes. 
The habits of the female stickleback would sat¬ 
isfy the strongest opponent of ‘woman’s rights,’ 
for she grows very fat, never assumes the brilliant 
colors of the male fish, and remains at home oc¬ 
cupied with domestic cares. Her warrior part¬ 
ner, however, does not throw the entire burden 
of the establishment on his weaker half. After 
clearing the neighborhood of all intruders, by 
using his sharp, well-directed spines much in the 
way that a Chinaman or Japanese wields his 
knife and rips up his enemies, he sets to work to 
build a nest and to rear a family. Look into your 
tank ; there he is—larger than the rest, clothed 
like a knight of old in a resplendent coat of mail, 
glittering with purple and gold. See how his 
eyes glisten, and how with every movement his 
colors change 1 His nest being carefully pre¬ 
pared, he gently allures his mate into it, where 
she deposits her eggs, and resigns them to the 
care of the hero of the knightly suit, who watches' 
over them with an anxiety known to few of the 
males in creation besides the male stickleback. 
He fans and freshens the water with his fins, and 
superintend? the first exit of the little fry with 
true paternal interest.. We ourselves have seen, 
in an aquarium kept by a lady in Aberdeen, a 
nest built by a fifteen-spined stickleback on a 
piece of rock covered with fine green sea-weed. 
For about three weeks the father fish never left 
this nest save to drive away or destroy all other 
fish that approached too near. When a stick 
was put into the water near the nest, the valiant 
guardian would fly at it open-mouthed and bite 
it with great fury. But all his care could not 
save his little ones from destruction. As soon 
as they escaped from the nest, they disappeared, 
being mercilessly swallowed in their infancy by 
other fish, or entangled in the tentacles of the 
sea-anemones — for this was a jw-water aquarium 
in which they were hatched. Probably the ex¬ 
periment would have succeeded better had the 
nest been isolated, and all the other inhabitants 
of the aquarium removed. 
Of course, in small domestic aquaria it is best 
to have small fishes as inhabitants. The tiny 
gold-fish we have mentioned as being very suita¬ 
ble, and the Prussian carp, found in ponds in 
the neighborhood of London, though not so 
bright a fish as the golden carp, has a very lively 
and pretty appearance. The minnow is a sportive 
little fish, and is seldom more than three inches 
long. It is generally to be bought at the fish¬ 
ing-tackle maker’s, as it is used by anglers as a 
bait for pike and other fresh-water fish. The 
loach and the gudgeon live well in aquaria ; we 
have them both, and have kept them alive and 
in health for three years. Fish in an aqairium 
should be well watched, and when apparently 
sickening, should be removed gently in the hand- 
net, and placed alone in fresh water, where they 
will often recover. If they, are doomed to die, 
■'A'lS’ot.'uelAldt'to' fui^ the risk of trieir doing so 
in the midst of their healthy companions. We 
always have a hospital for our sickly pets. 
But although at the first glance at an aquarium 
one is attracted by the active little fishes swim¬ 
ming amongst the bright green weeds, we who 
wateh them daily, and spend many leisure half- 
hours in attending to them, in clearing away the 
overgrowth of weeds, and making subaqueous 
highways and paths for their better movements, 
know that the curious water-spider (Argyroneta 
aquatic ) with his crystal bubble, the queer little 
water-flea ( Daphnia ), and the odd-family of 
water-beetles, are even more interesting, because 
their habits are more obscure than those of the 
funny tribe. The spider’s brilliant bubble, 
which surrounds his body, enables him to rise 
through the water and float about at his pleasure. 
Diving, he constructs a sort of nest at the bottom 
of the water. When he wishes to take a journey 
and ascend to higher regions, he inflates his 
transparent jacket and floats away ; and when 
wishing to remain on firm ground, dispenses 
with his air-bubble, and looks like an ordinary 
spider. He is an easy prey to fish, and cannot 
well be kept with them, though he may often 
escape for a long time. 
The great water-beetle (Dyticus marginalis) is 
a well-known beetle in our ponds and streams. 
It is the most ravenous of its kind, and will at¬ 
tack everything eatable ; even the stickleback is 
no match for it, and tadpoles it devours by doz¬ 
ens in a day. Its lame are as destructive and 
tyrannical as itself, and have got the character¬ 
istic name of ‘water devils.’ The little whirlgigs 
( Gyrinidce ) should not be neglected; they are 
often seen twirling round like opera-dancers on 
the surface of the water, and are among the 
earliest harbingers of spring. Beetles fly at night, 
and unless the aquarium be covered, some of 
them may take a moonlight-flitting and be lost. 
The water scorpions and the water boatmen form 
pleasant little objects in the water, and the larvae 
of various other species of insects may be kept 
with interest. It is possible also to get a little 
colony of caddis-worms in their curious little 
cases, and to watch their habits and ways with 
much pleasure. But to those who really take 
interest in matters microscopic, and are furnished 
with a microscope even of small pretensions, the 
aquarium will be a costant source of study and 
delight. The Hydra family, the Polyzoa, &c. 
may be nursed, and reared, and' propagated in 
very small water space, and are a perpetual sup¬ 
ply of interest. Many earnest observers have a 
microscope so fixed as to catch the surface of the 
glass of a tank, and to revolve so as to be able 
to fasten just over any little object to be observed. 
Diatoms, animalcules, and curious plant-like 
cells, abound in fresh water, and grow and in¬ 
crease abundantly if left unmolested by larger 
creatures. Volvox globalor, a dark green, mov¬ 
ing and revolving globe, once thought to be an 
animal, but now regarded as a plant; and 
Euglena viridis, which some suppose to be a 
plant, others an animal, and which often gives 
to water the appearance of grean pea soup. 
Amongst animalcules, we have the curious sun 
animalcule, which has the power of suddenly 
contracting its tentacles, and thus leaping ^.bout 
in the water. Trie microscope shows that it has 
no mouth or stomach, but has the habit of press¬ 
ing food into its substance by means of its tenta¬ 
cles. The ‘ bell animalcules ’ or Vortieellce, are 
likewise too small to be distinguished by the 
naked eye. In some species, more than one 
individual is found on a single stem, forming ex¬ 
ceedingly beautiful objects under the microscope. 
The stalks of these Vorticellte are thinner than 
the finest spider’s thread, and have the power, 
while outstretched, of instantaneously contracting, 
so that a large mass, expanding over the whole 
field of the microscope, suddenly disappears, 
and, ‘ like the baseless fabric of a vision, leaves 
not a wrack behind.’ A little patience, and the 
„ beaudfel JS/m 'Vd** 
expand themselves in all their beauty. Then we 
have the Rotifers , with their curious cilia, which 
have the appearance of little wheels ever in mo¬ 
tion ; and the Polygastrica (many-stomached), 
so cleverly described by Professor Ehrenberg, 
who, with the most imperfect microscope, made 
careful observations on this group of animalcules, 
and determined to his own satisfaction that the 
little spots in their interior are, iu reality, stom¬ 
achs. He fed them with a little indigo or car¬ 
mine, and then these spots became colored blue 
or pink, showing, as he then thought, that they 
were many-stomached. Recent observers doubt 
his conclusions, but they are nevertheless sug¬ 
gestive and interesting. Then we have the curi¬ 
ous little Hydra in almost every stagnant pool 
in the summer time, and we have successfully 
kept a colony of these singular creatures at¬ 
tached to a root of valisneria, which throve well 
in a long glass vase—a confectioner’s covered 
jar. Well is it named ‘Hydra,’ after the fabled 
monster that multiplied its heads as fast as Her¬ 
cules cut them off, for no cutting up is able to 
destroy this persistent creature. Every individ¬ 
ual fragment very shortly becomes a perfect 
Hydra, which attaches itself to a bit of stick or a 
plant, sending out its long semi-transparent green 
tentacles to clutch unwary prey that may stray 
towards it. From this very jar we have often 
taken bits of valisneria leaf, to make a pretty 
and instructive object under the microscope, for 
I no plant shows so well the circulation of fluid 
through the cells and tissues of a leaf. Water 
plants, being of less dense tissue than those that 
grow in the air, are peculiarly adapted for this 
purpose. 
In furnishing our aquarium we must not for¬ 
get the scavengers, of which we have before 
written. Certain varieties of Mollusca—snails 
with shells, in fact—live plentifully in fresh wa¬ 
ter, and have large appetites for green weeds. 
They are most useful in clearing off the growth 
of green confervae, which gathers on the sides of 
the glass when exposed to light; but care must 
be taken that their grazing is confined to that 
