LIFE CYCLE OF HYDATINA SENTA 



145 



in this experiment were reared under conditions as nearly alike 

 as possible. 



The objection may be raised that in making these crosses, the 

 respective environments of the two pure lines were necessarily 

 mixed, and that the pure line bred from one of the resting eggs 



TABLE 35 



Comparison of two distinct pure lines of Hydatina senta with another pure line derived 

 from a cross between the first two, all being bred under like conditions. A and 

 B are separate experiments. 



Experiment 



New York Pure Line 



NO. OF 

 GENERA- 

 TION 



NO. OF I NO. OF 



cf 9 ! 9 9 



Pure Line From Cross 



NO. OF 

 GENERA- 

 TION 



iKO. OF NO. OF 1 



0^9 9 9 



Baltimore Pure Line 



NO. OF 



GENER.^- 



TION 



NO. OF NO. OF 



^^9 9 9 



