22 
THE NEW YORK AQUARIUM JOURNAL. 
FISH CULTURE AT THE AQUARIUM. 
Tlie apparatus in use in the Aquarium for 
fish culture is of the latest and most approved 
pattern, and consists of a large wooden reser- 
oir divided lengthwise by a partition, in 
which are placed frames covered with a woolen 
screen which filters the water before it passes 
over the eggs. The hatching troughs, five in 
number, are placed with their heads abutting 
the reservoir and are supplied by brass cocks. 
In the troughs are placed frames covered 
with wire cloth, which, with the wood work, 
and in fact every part that the water comes 
in contact with, is coated with coal tar, which 
not only keeps the wire from rusting, but also 
prevents the jelly-like sap that always appears 
in new pine wood when under water, from 
exuding, while it also is a barrier to any 
vegetable growth upon it. 
The eggs are laid upon these wire screens, 
of which several layers can be used in each 
1 rough, thus increasing their capacity. Only 
two troughs are in use at present and are 
filled with the ova of the California Salmon 
which were presented by Prof. S. F. Baird, 
the Commissioner on Fisheries for the United 
States. They were obtained from his Salmon 
breeding ranch on the McCloud River, Cali¬ 
fornia, in charge of Mr. Stone, the Deputy 
Commissioner. This variety of Salmon is 
called by Naturalist’s the Salmo Quinnat, and 
from its being capable of passing through 
water that in Summer reaches a temperature 
of 80 degrees Farenheit on its annual migra¬ 
tion from the sea to its fresh water breeding 
grounds above, and which would kill its con- 
genor of the Adantic Coast, is more valuable 
than the ( latter for stocking all our rivers 
south of the Connecticut. Many millions of 
the eggs have been taken, hatched and dis 
tributed by Prof. Baird in the past two years, 
but as it requires three years for this fish to 
reach maturity and return to the place where 
it was deposited, it is too soon to see the re¬ 
sults yet, though many young have been 
caught during the first year that they remain 
in fresh water. 
The eggs are obtained from the living fish 
by pressure of the hand upon the abdomen, 
and such is the delicacy of touch and knowl¬ 
edge of condition acquired by an expert that 
a fish is seldom killed by them, and Mr. 
Mather states that he has taken eggs from the 
same trout for five years in succession with¬ 
out injury to them. After the eggs are taken 
in a pan that has been merely wet, a male 
fish is manipulated ,‘n the same manner over 
the eggs and in a few minutes after the addi¬ 
tion of a little water, the fecundation is com¬ 
plete and the ova is placed in a trough where 
it remains for three or four weeks, until the 
eyes can be distinctly seen and all the unim¬ 
pregnated ones picked out, when they are 
packed in a box with a layer of fine, living- 
moss, and a layer of eggs alternately until 
full—this box is then packed in a crate of hay 
or box of sawdust to keep it from changes of 
temperature and sent by express to any part 
of the world. The eggs of the California 
Salmon are the largest now handled by fish 
culturists, measuring nearly one-third of an 
inch in diameter, and as the eggs of any fish 
average about one size for each°species, they 
are measured to find the number of thousands 
t iken. 
It takes from forty to sixty days to hatch a 
Salmon egg, accordingto the temperature; a 
high one, say 70 degrees, hatching very quick¬ 
ly but leaving the fish weak. The best tem¬ 
perature is that of the spring water in which 
they are laid, perhaps, from 45 to 50 degrees. 
After hatching, the yolk of the egg remains 
attached to the abdomen for about thirty 
days, and at first is so large that the little 
embryo cannot swim with it, but it is gradu¬ 
ally absorbed and when all taken up the 
Salmon takes food for the first time. This 
rule is good for all the varieties of Salmon 
and T -out. Som ■ fish, as the Whitefish and 
Shad, can swim as soon as hatched, although 
the sac is attached in the same manner. 
Later in the season the other troughs will 
be occupied by the Land-locked Salmon from 
Maine, a fresh water variety, the Lake Trout, 
the Brook Trout and the Whitefish ; the^e 
are all winter-spawning fish and hatch slowly 
on the trays. Shad eggs require an entirely 
different treatment, which will be explained 
in a future number of the journal. It is the 
intention of the Manager of the Aquarium to 
stock some of the rivers with the fish hatched 
here, thus making it a useful as well as in¬ 
structive, and a valuable adjunct to the Fish 
Commission, and to this end he has engaged 
the services of the well-known Fish Culturist, 
Mr. Fred. Mather, to superintend this Depart¬ 
ment, for which he is well qualified by his long 
experience as a breeder of trout for a long 
period at Honeoye Falls, N. Y., and his work 
of Salmon and Shad hatching for the past 
three years for the Virginia, and United 
States Fish Commissions. 
This is one of the most interesting features 
of the Aquarium, both to the Naturalist, the 
Embryologist, and'the casual visitor. The 
newlv-hatched fish is so transparent that the 
beating of the heart and circulation of the 
blood can be seen with the naked eye, and the 
development from the embryo to the perfect 
fish observed from day to day, and a wonder¬ 
ful transformation it is, for at first the little 
creature is as unlike the parent fish as a tad¬ 
pole is unlike a frog; the mouth which at 
iirsf iamly* fftted-.tajoass water.jto the gills is 
changed so as to take food, and the embryonic 
fin which, rising in the middle of the back, 
runs around the tail to the anal fin, is ab¬ 
sorbed, leaving the true fins more and more 
distinct each day. A few years ago Prof. 
Agassiz discovered that the Salmon had a 
second heart situated in its tail which was 
most visible at the third day and disappeared 
about the tenth. 
COD—G adus Morrhua, 
Every one is familiar with this fish from the 
number almost always present in the fish-shops 
and markets. Lying on a slab with huge head, 
gulf-like mouth, with pendant barb and dull 
staring eyes, it is by no means a lovely object. 
Judging it by its appearance in death, one 
would suppose it a mere stupid mass of ani¬ 
mated matter, whose only purpose in creation 
was to eat incessantly, and be eaten when 
gorged enough. But the Cod, on the contrary, 
is a most intelligent fish, capable of friendship 
with its guardians and feeders. 
In Mr. Buckland’s work, “Familiar History 
ol British Fishes,” page 126, published by the 
Society for the Promotion of Christian Knowl¬ 
edge, 77 Great Queen Street, Lincoln’s Inn 
Fields, is a description of the tame Codfish at 
Port Logan, Scotland. These fish are kept in a 
pond cut out of the solid rock, the entrance and 
exit of the salt water being guarded by an iron 
grating. The fish are kept here, and taken when 
required for the home use of the proprietor, 
General McDonald, late 2d Life Guards. 
Very remarkable substances have been at 
times found in the stomachs of Cod—for instance, 
a large piece of ship’s tallow candle, a bunch of 
keys, a guillemot, feathers and all, and whitings 
to the extent of eight pounds at a time. 
Records are also known of the large size of 
the Cod. One was taken at Port Knocke which 
weighed 60 pounds. This fish had no melt or 
roe, and no food in the intestines. The length 
was four and a-half feet, and three feet- round 
the thickest part. The head was one and a-half 
feet in length, and weighed 15 pounds. This 
was undoubtedly the largest Codfish ever taken 
in British waters. Cod’s food consists of shell¬ 
fish, crabs, and worms; but, as it is perpetually 
hungry, it will devour smaller fish, as herrings, 
sprats/lampreys. It is caught with a hook and 
line baited with some of the above mentioned fish, 
and such is the enormous quantity taken, that 
the celebrated fishing ground called the Banks 
of Newfoundland, gives employment to a fleet 
of boats, whose gross earnings amount towards 
one million dollars. Its liver contains a valu¬ 
able oil, greatly used in cases of debility. Cod 
are very prolific; a Cod’s roe weighing seven 
and three-quarter pounds will contain nearly 
7,000,000 eggs. These are deposited on the 
surface of the water, as has been proved in the 
Brighton Aquarium. In about sixteen days the 
young fish are developed, though the open sea 
is a very insecure place for baby-fish ; a multitude 
must survive to furnish the perennial supply our 
fishermen bring to shore. Codfish can be kept alive 
a long time. At Fulton Market they are placed 
in perforated boxes and moored in the docks. 
THE SEA SWALLOW. 
Daclyloplerus volitans. 
In tank c we find this bird-like member 
of the finny tribe. Upon examination the 
head appears to be encased in a bony armor, 
while the remainder of the body is covered 
with minute scales, that form a strange con¬ 
trast to the former. It, however, needs but 
little defense, as the pectoral, or side fins are 
developed to a wonderful extent, rendering it 
able to rise from the sea and skim over the 
surface after the fashion of its terrestrial 
namesake. With such force do they move, 
that they have boarded a vessel and striking 
down. They belong to the curious family of 
Gurnards, and strange tales are told of sounds 
that they produce under water, but the ques¬ 
tion is still open to the speculations of physi¬ 
ologists. Prof. Baird was fortunate in wit¬ 
nessing this phenomenon, and expressed an 
opinion that it originated in the belly of the 
fish. Dr. Davy discovered flat, grinding teeth 
in the oesophagus of the Red Gurnard, and it 
is probably by a peculiar movement of these 
that the strange language? is produced. In 
appearance, the Swallow is very attractive, es¬ 
pecially in the sun light, when the beautiful 
bluish iridescent colors of the “wings,” and 
the flesh colored ventral fins come out in bold 
relief and mark it as one of the most attrac¬ 
tive of its kind. It is found occasionally in 
New York, and has a wide geographical 
range. It feeds upon the small cruestacea 
that the sea affords. 
THE SEA RAVEN. 
Hemitnpterus Americanns. 
^ Closely connected by family ties to the Sea 
Swallow, is the Sea Raven, several fine speci¬ 
mens of may be seen In table tauk d, and it is 
always surrounded by doubtful admirers who 
speculate as to the ownership of the wonderful 
tufts, “bobs,” and masses of disjointed flesh that 
seem to cover it, and the visitor is not rarely 
led to believe that by a system of inactivity it 
has been covered with a growth of aquatic 
plants and verdure. But they are all “real,” 
and this fantastic ornamentation is the bona 
fide work of nature. The specimens in this 
tank were captured near Gay’s Head, Mass., 
and are there known as Sculpins, and make 
sad work with the lines of the patient fiisher- 
man. It is subject to great variation of color, 
and the Aquarium will soon possess speci¬ 
mens, varying from the rich, russet brown to 
a bright carmine yellow and red. They feed 
entirely upon smallfish, but do not reject any 
morsel that their capacious mouths can cover. 
