Series ^""'^ 



retarded 



<- i 



60-72 



60 



54 



4S 



42 



Fig. 6 Cut showing relative sizes of imagines as produced by" feeding experiments. Number of the 

 series on the left, and number of hours that the larvae were permitted to feed on the right. See explana- 

 tion of series on pp. 68 to 72. 



