EFFECTS OF INBREEDING AND CROSSBREEDING. 



25 



1906 /908 1910 /9I2 /9/4 /9I6 19/8 1920 

 200 



A ,x 



S±Z-^l 



B 



/SO 



/60 

 /40 



\ /oo 



^ 80 



60 



40 



20 







Fig. 6.— The average gain between birth and 33 days. Inbreds (A) and controls (B), 1906 to 1920. Cor- 

 rected for effect of size of litter as in Figure 1. 



J906 /908 /S/O /S/2 /S/4 /9/6 /S/O J920 

 280 



260\ 1 -X 1 A 1 1 JB 









* 



\ 











\ 



^ A 



% 



% 





y 







\ / 





\ » 



\ » 

 \ % 



* 



* 













y 

















































































































































240 

 220 

 200 

 /SO 



\ WO 



\ 120 



/OO 



so 



60 

 40 

 20 



Fig. 7.— The average weight at 33 days. Inbreds (A ) and controls (B), 1906 to 1920. Corrected for effect 



of size of litter as in Figure 1, 

 106851°— 22— Bull. 1090—^-4 



