52 



BULLETIN 1121, U. S. DEPARTMENT OF AGRICULTTJEE. 



Table 18. — Average birth weight in grams of all young, bom dead or alive. 



JAverage in litters of each size and the index (litters of 1, 2, 3, and 4 weighted 1, 3, 3, and 1, respectively).. 

 Inbreeding and crossbreeding experiments, 1916-1919.] 



Experiment. 



Size of litter. 



Index. 



1 



2 



3 



4 



5 



6 



7 



2 



86.0 

 101.9 

 98.1 

 96.5 

 85.8 

 93.0 



72.0 

 80.8 

 80.0 

 84.5 

 72.6 

 75.3 



60.1 

 68.4 

 66.4 

 70.1 

 63.0 

 64.9 



50.5 

 .59.2 

 57.4 

 56.6 

 50.4 

 53.5 



44.5 

 50.7 

 52.5 

 50.4 

 53.5 

 43.6 







66.6 



13 



39.5 





76.1 



32 





74.3; 



35 







77.1 



39 



37.8 





67.9- 



Other 





70.9 











Inbred 



93.0 

 97.7 

 107.0 

 100.3 

 101.8 

 104.2 

 104.5 

 104.5 

 106.7 



77.0 

 77.6 

 86.0 

 95.8 

 86.9 

 84.4 

 84.8 

 90.8 

 87.5 



65.3 

 64.4 

 72.5 

 75.7 

 70.2 

 69.8 

 72.9 

 78.3 

 79.0 



54.7 

 53.9 

 63.3 

 65.9 

 59.1 

 63.5 

 61.0 

 66.0 

 62.8 



48.9 

 48.5 

 56.6 

 60.3 

 51.1 

 51.7 

 58.5 

 56.5 

 59.2 



38.9 





71.8 



CO 





72.2 



CA 







80. T 



AC 



48.8 

 71.2 





85.1 



CC 





79.0 



CI 





78.8 



C2 







79.8 



€h 



63.3 

 54.0 





84.7 



CG 





83.6 









B 



101.2 



86.9 



71.8 



61.7 



57.0 



54.7 



24.5 



79.9 







Table 19. — Average birth weight, in grams, of young which were raised to weaning. 



{Average in litters of each size and the index (see Table 18). Inbreeding and crossbreeding experiments, 



1916-1919.] 



Experiment. 



Size of litter. 



Index. 



1 



2 



3 1 4 



5 



6 



7 



12 



94.9 

 110.8 

 103.5 

 104.5 



91.1 

 101.3 



76.9 



88.7 

 84.0 

 87.3 

 76.4 

 80.4 



65.8 58.4 



75.2 I 67.1 



70.9 ' 63.1 

 74.4 i 63.6 



68.3 ; 60.8 



69.4 : 58.8 









72.7 



13 



63.9 







83.7 



32 







78.9 



35 



63.1 

 60.5 

 56.5 







81.6 



39 







73.3 



Other 







76.1 











Inbred 



100.9 

 101.9 

 110.5 

 111.4 

 103.6 

 107.0 

 105.3 

 110.5 

 111.9 



82.1 

 82.9 

 89.9 

 98.4 

 89.5 

 85.6 

 86.7 

 91.3 

 91.3 



70.4 ! 61.9 



71.3 ; 61.9 

 74.1 , 69.0 



77.4 i 67.9 

 72.3 67.8 

 74.3 ; 67.2 

 77.6 65.0 



74.8 ' 74.0 



82.9 70.0 



62.0 

 63.2 

 60.7 

 63.7 

 65.3 

 C3.5 

 59.6 

 63.0 

 67.6 





77.6 



CO 





78.3 



CA 





83.9 



AC 



55.5 

 74.5 





88.3 



CC 





82.1 



CI 





81 7 



C2 



............... 



82.9 



CL 



58.9 

 66.7 





85.4 



CG 





88.1 









B 



111.5 



90.8 



75. 67. 7 



63.0 



60.0 





84.6 







