42 



GENETIC STUDIES OF RABBITS AND RATS. 



Table 32. — Comparative size of the two sexes in the several groups of cross-bred rabbits. 



Group. 



Fi, PXH 

 Fj. PXH 

 Fi, HXF 

 Fo. HXF 

 Fi, PXF. 

 F2. PXF. 



Weighted mean*. 

 Per cent greater . . 



Tibia. 



Males. 



CI 



93 . 65 

 90.07 

 100.20 

 97.78 

 96.59 

 94.29 



94.72 

 1.58 



Females. 



a 



91.65 

 89.68 

 97.90 

 96.88 

 95.75 

 92.11 



93.24 



Femur. 



Males. 



a 



ei 

 s> 



78.78 

 76.45 

 87.95 

 84.90 

 83.52 

 80.87 



81.35 

 1.10 



Females, 



a 



a 



71 Ab 

 75.97 

 86.68 

 84.63 

 83.15 

 79.53 



80.46 



Humerus. 



Males. 



0) 



63.63 

 61.15 

 69.45 

 67.36 

 66.41 

 64.03 



64.66 

 0.57 



Females. 



1^ 



62.20 

 60.73 

 68.26 

 67.33 

 65.93 

 63.88 



64.29 



Skull-length. 



Males. 





70.50 

 69.18 

 79 48 

 76.37 

 75.59 

 73.14 



73.42 

 0.16 



Females. 





69.95 

 68.80 

 78.58 

 76.66 

 75.50 

 73.12 



73.30 



Group. 



Fi, PXH 

 F2, PXH 

 Fi, HXF 

 F2, HXF 

 Fi. PXF. 

 F2, PXF. 



Weighted mean* 

 Per cent greater. 



Anterior 

 skull-width. 



Males. 





39.90 

 38.65 

 43.63 

 41.91 

 42.48 

 41.28 



41.05 

 2.03 



Females. 



a 



C3 

 a) 



38.65 

 37.94 

 42.36 

 41.38 

 42.13 

 40.32 



40.23 



Posterior 

 skull-width. 



Males. 



a 



40.23 

 38.61 

 43.88 

 42.49 

 42.84 

 41.20 



41.21 

 2.46 



Females, 



10 

 29 

 9 

 33 

 13 

 61 



a 



38.35 

 37.90 

 42.70 

 41.50 

 41.58 

 40.38 



40.22 



Ear-length. 



Males. 



15 

 24 

 8 

 37 

 14 

 67 





9.54 

 9.25 



.45 

 .50 



10.91 

 10.69 



10.55 



Females 



10 

 31 

 9 

 33 

 13 

 64 



13 



9.42 

 9.16 

 11,66 

 11.65 

 10.97 

 10.71 



10.58 

 0.20 



Weight. 



Males. 



a 



c3 



1,957 

 1,560 

 2,694 

 2.401 

 2,469 

 2,080 



2,110 



Females. 



a 

 a 

 a> 



2,005 

 1,704 

 2,886 

 2,531 

 2,545 

 2,176 



2.221 

 5.26 



* The weighted means were obtained by counting each male mean the same number of times 

 as each female mean, the number of individuals assumed for the purpose of the computation 

 to occur in each sex of each gioup being as follows: Fi, PXH, 15; F2, PXH, 30; Fi, HXF, 10; 

 Fj, HXF. 33; F,. PXF. 15; F2. PXF, 65. 



