376 



H. G. MAY. 



In the seventh generation the mean of the stock had been reached 

 by the females, but the males were still slightly lower. Taking 

 the mean of the male and female averages more uniform results 

 appear to have been obtained. In that case the first generation 

 shows no change, the second and third generations show a gradual 



A A 



A A 



f6 



72<J<J 

 9699 



f 6, reverse 

 d if 5- 14 



4599 



tl 

 150<J< 



19399 



f 7, reverse 

 214<5<5 

 22599 



f 5, reverse 

 u4f4-19 



2892 



A , A 



J 1 1 1 1 1 I 1 



f6 



186J<J 

 21892 



f 6, reverse 



u4f5-23 



28<Jd 



3329 



, A , A i 



ud aerlea f 1 



uadtf 



14l9i 



A . A 



30 70 110 150 190 230 270 30 70 110 150 190 230 270 310 350 390 430 



FIG. $B. 



FIG. 5. Curves showing the effect of selection for generations in Ba. These 

 curves are plotted on a scale of one hundred. Parents are indicated by smaller 

 curves at the top. In other respects the curves are like those of Fig. 2. 



