324 FARM ANIMALS 
spawned in the nesting place and if properly fertilized 
and not destroyed by other fish of the same tribe or by 
other natural enemies a very large family of young fry 
results. After breaking through its shallow shell and 
emerging from the egg the young fry is still encumbered 
with the yolk sac, which extends all along the abdomen. 
The yolk is the baby fish’s nourishment and as long as it 
remains no other food is required. The length of time 
the sac remains on the iry varies with different kinds of 
fish. The fall-spawning varieties possess the yolk sacs 
for a month or two, but those varieties that cast their 
spawn in the spring do away with their little nursing bot- 
tles in a few days. Eggs from fish that spawn in the 
spring hatch in a short time and the young are soon able 
to escape and hide from their enemies. Fall spawners, 
like the brook trout, require two or three months for 
hatching and leaving the yolk. It is evident that all 
tribes subject to slow development are most liable to be 
destroyed during their days of infancy and early youth. 
Fish hatcheries—Most states now support establishments in 
which are artificially hatched many millions of fish eggs for stock- 
ing streams, lakes, rivers and ponds. These meritorious enter- 
prises are supported by public funds. When the small fish have 
reached the proper size they are furnished to the public at cost or 
free. The federal government also hatches vast numbers of dif- 
ferent varieties of fish, which are given to interested persons on 
request. The application for fingerlings for stocking purposes re- 
quires a description of the pond, lake or stream and the kind of 
fish desired. Those in charge give suggestions as to what variety 
is most suitable and directions as to handling, care and culture. 
