View of posterior surface of 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig 
g. 
Fig. 
65. 
66. 
No. 
No. 
No. 
No. 
No. 
No. 
No. 
No. 
8987, 
12654, 
12668, 
16385, 
19229, 
210, 
4347, 
12101, 
Castor 
Castor 
Castor 
Castor 
Castor 
Castor 
Castor 
Castor 
PLATE 12 
the left femur; about two-fifths natural size. 
subauratus. 
subauratus. 
subauratus. 
subauratus. 
fiber. 
canadensis phaeus. 
canadensis belugae. 
canadensis leucodonta. 
Note that the epiphysis of the great trochanter forms an angle nearer ninety 
degrees with the shaft, in subauratus and fiber than in canadensis; that in fiber 
and canadensis the intertrochanteric line is more clearly defined than in sub- 
auratus ; that the lesser trochanter of fiber and subauwratus has an epiphysis, but 
that it does not occur in the forms of canadensis; that the third trochanter of 
canadensis is sharper than that of fiber or subauratus. 
[114] 
