78 
FISHES 
saved from extermination and their numbers largely in¬ 
creased, the governments of the world have established 
hatcheries where fish are raised in great numbers. 
In these hatcheries the eggs are taken from the female 
and placed in a jar, and the mass of minute sperm cells or 
The large mass under the neck is the yolk or food used by the young 
fish before it is able to capture its own food. Note that there are no fins 
and that the gills are not well developed. 
“ milt ” is taken from the male and poured over the eggs, 
so that practically all the latter hatch. Then by giving the 
developing eggs protection, and the young fish sufficient 
and proper food, nearly all these eggs develop into active 
fish and the great loss that comes to the fish developing in 
Figure 67. —Young Fish Seventeen Days After Hatching. 
It has absorbed the large mass of food and the fins and gills are large 
enough to be used by the young fish which must capture its own food 
from now on. 
their natural environment is prevented. When they are 
able to take care of themselves, these fry, as the young 
hatchery fish are called, are taken to natural feeding grounds. 
In New York State and most other states there are state 
hatcheries where such fish as shad, pike, lake trout, salmon, 
brook trout, and others are raised by millions. 
