8o THE OYSTER. 



ternal conditions of life, and the birth-rate has very 

 little to do with it. 



In the case of the oyster, the adult is well protected, 

 by its shell, against the attacks of most of the enemies 

 which are found in our waters, and as its food is 

 very abundant and is brought to it in an unfailing sup- 

 ply by water, it is pretty sure of a long life after it 

 has reached its adult form ; but the life of the young 

 oyster is very precarious : that of the young American 

 oyster peculiarly so, since it is exposed to many ene- 

 mies and accidents at the time when it is most helpless. 

 The oyster of Northern Europe lays from one to two 

 million eggs, while our oyster lays about ten times 

 as many, but the protection which is afforded to the 

 young European oyster by the shell of the parent more 

 than balances the greater birth-rate of our oyster. 



The most critical time in the life of the American 

 oyster is undoubtedly the time when the egg is dis- 

 charged into the water to be fertilized, for the chance 

 that each egg which floats out into the bay to shift for 

 itself will immediately meet with a male cell is very 

 slight, and infinite numbers of eggs are lost from this 

 cause. The next period of great danger comes as the 

 little embryos begin to swim and crowd to the surface 

 of the water. They are so totally defenseless and are 

 so close together that a little fish swimming along with 

 open mouth may swallow thousands in a few mouth- 

 fuls, and I have found that at this time a sudden fall of 

 temperature is fatal to them, and a cold rain may 

 destroy millions. As soon as they are safely past this 



