198 THE MEANING OF EVOLUTION 
of the nucleus of the cell and carrying the determi- 
nants which were to decide one-half of its future char- 
acters, penetrated this egg and fused with its nucleus. 
This was filled with the determinants of the charac- 
ters inherited from the mother. Of course many of 
the eggs, of which probably there are a thousand, 
must have escaped fertilization. There are doubtless 
a thousand sperm cells that went to utter waste for 
one which found an egg to fertilize. These eggs 
nestled in the crevices between the stones in the warm 
water of the edge of the lake. Here the sun could 
easily penetrate to the bottom and hatch them. The 
little fish, still guarded by one hovering parent, swam 
around in the water long before the yolk of the egg, 
containing its large amount of food, had been ab- 
sorbed into the tissues of the young fish. This fatty 
store made the abdomen of the fish in which it lay 
protrude enormously. Gradually the fish grew larger 
and the yolk grew smaller until all had been consumed. 
Soon the fish began to forage for himself and no 
longer to demand or care for the company and pro- 
tection of its parent. The little sunfish is highly 
favored among his comrades in having any care what- 
ever by the parent. In the case of most fishes the 
female, swimming slowly over the bottom, deposits 
her eggs, which are fertilized by the male, which 
follows behind her. After the eggs have thus been 
