22 



BULLETIlSr 1121, U. S. DEPARTMENT OF AGEIGULTUEE. 



while CG is no better than the second generation crossbreds. It is 



not safe to conclude that the selection for weight has had any effect. 



The birth weights of the young raised in the inbred families and in 



Experiments CO, CC, Cl, and B are compared for each size of litter 



K/0 



I 



J: 



















0/?^MS 



B 











Co 





/iO-'P 









^y 



nc/^ 



^/ 



yCG 1 



13 









,x'V^, 



y^^ 





^ 





35 







^'' 

 x" 



^^ 



ex? 





"^ 



C2,CL 



OI 





x''' 



^^^^.^iii^ 



CO 











32 

















77.6— 



39 



















2 



















Fig. 12.— The birth weight of the young raised to 33 days, 1916-1919. Indices correcting for eflects of 

 size of litter and seasonal conditions (Table 2). (See Fig. 8 for explanation of symbols.) 



in Figure 22. The great effect of size of litter on birth weight is 

 illustrated. Otherwise the conclusions are the same as those drawn 

 from the indices. 



20 



\/0 

 \ 

 ^ O 















CC 



CL. 



< 4^4-9 

















13 

 35 



c 





y 



^ 



/RC 

 CX? 



CI 





C2 



01 



^ 



> 



y^ 











3.<S4^— 



39 



/^ 













2 



/ 

















-JO 



■20 



Fig, 13.— The rate of gain between birth and 33 days, 1916-1919. Indices correcting for effects of size 

 of litter and seasonal conditions (Table 2). (See Fig. 8 for explanation of symbols.) 



DAILY GAINS. 



We have seen that the results for birth weight are similar to those 

 for percentage born ahve. The results for daily gain between birth 

 and weaning (Fig. 13) are, on the other hand, more like those for 



