138 



A. FRANKLIN SHULL 



TABLE 31 



Showing number of male- and female-producers in the progeny of three sister indi- 

 viduals of Hydatina senta, one line being bred in spring water, the other two in 

 solutions of beef extract of different strengths. 



Experiment XXX. From three sister females, three Unes were 

 reared, starting on July 18, 1910. One line was reared in a 0.02 per 

 cent solution of the crude creatin in Great Bear spring water, one 

 in a 0.025 per cent solution, the third in spring water alone. Table 

 32 shows the three pure lines in detail. 



Experiment XXXI. This is a repetition of Experiment XXX, 

 but with weaker solutions of creatin in both parts, a 0.01 per cent 

 and a 0.015 per cent solution being used. In both of these experi- 

 ments some of the eggs laid in the creatin solution did not hatch 

 in the usual short time required in spring water. In such cases the 

 creatin was diluted after the death of the parent, and many of the 



