152 



A. FRANKLIN SHULL AND SONIA LADOFF 



Ion, but to have added a substantial balance of male-producers 

 on the bouillon side. 



TABLE 19 



Showing the effect of oxygen and bouillon on one line, as contrasted with a line not 

 subjected to either. Bouillon, even in dilute solutions, has been shown to reduce 

 the number of male-producers {see table 9). In this experiment, oxygen coun- 

 teracts the effect of the bouillon, and actually increases the proportion of male- 

 producers above that in the control line 



Experiment 20. Oxygen counteracting strong manure solution. In 

 this experiment only the parents were reared in the manure solution, 

 the offspring being in all cases reared in spring water. The parents 

 to be used for both experiment and control were placed in manure 

 solution in the afternoon; the next morning one lot (the control) was 

 transferred to a new dish of manure solution, the other lot was transferred 

 to manure solution which had been saturated with an atmosphere 

 of which 40 per cent was oxygen. The former lot was kept in air, 

 the latter under a bell jar in an atmosphere of 40 per cent oxygen. 

 At the end of 24 hours the parents were removed from both dishes. 

 All eggs laid in the 24 hour period were allowed to hatch where laid, 

 the young females being then removed to spring water. 



The young females from each lot of parents were transferred 

 to spring w^ater on two successive days. Wlien the parents 

 were removed, those eggs that were laid in the first seven to ten 



