THE OYSTER. 8l 



stage and have scattered and begin to swim at various 

 depths, their danger from accidents and enemies is 

 greatly diminished, and their chance of reaching ma- 

 turity increases rapidly. Experiments which I carried 

 on many years ago show that there is no difficulty in 

 rearing them up to this point in captivity, and that in 

 a very small aquarium millions of them may be safely 

 carried past the most precarious part of their lives 

 and freed from their greatest dangers. 



Although the mortality at their early stages is so 

 excessive, the number of young oysters which pass 

 through them in safety without artificial help is very 

 great, and if there were no other dangers or uncertain- 

 ties there would be no need of measures for their pro- 

 tection. As they swim to and fro in the water they 

 are carried to great distances by the tides and currents, 

 and they reach all parts of the region of water within 

 several miles of the parent bed. In a favorable season, 

 any plant, or bush, or piece of driftwood which floats 

 near an oyster-bed becomes covered with small oys- 

 ters, although the nearest bed may be miles away ; and 

 the fact that young oysters may be thus collected in 

 any part of our bay shows that they are distributed 

 everywhere, and we might expect the adults to have an 

 equally general distribution. This is by no means the 

 case, and nothing can be farther from the truth than 

 the idea that the bottom of the oyster area is uniformly 

 covered with oysters or ever has been, although it is 

 quite true that oysters may be reared artificially over 

 nearly the whole of it. The idea that it is only neces- 



