Life Cycle of Hydatina Senta 



339 



TABLE XIII 



Showing the number of male- and female-producers in a series of families of Hydatina senta bred from the 

 first -born (whenever possible), and another series from the last-born, of each successive generation. 



TABLE XIV 



Showing number of male- and female-producers in a series of families of Hydatina senta bred from the first- 

 born, and another series from the fifteenth-born of each successive generation, all being the progeny of a 

 single individual. A and B are separate experiments. 



THE JOURNAL OF EXPERIMENTAL ZOOLOGY, VOL. 8, NO. 3. 



