PLATE 7 
Lateral view of the left scapula; about one-half natural size. 
Fig. 17. No. 8987, Castor subauratus. 
Fig. 18. No. 12654, Castor subauratus. 
Fig. 19. No. 12668, Castor subauratus. 
Fig. 20. No. 16385, Castor subauratus. 
Fig. 21. No. 19229, Castor fiber. 
Fig. 22. No. 210, Castor canadensis phacus. 
Fig. 23. No. 43847, Castor canadensis belugae. 
Fig. 24. No. 12101, Castor canadensis lewcodonta. 
Note that the suprascapular border is more nearly straight in fiber and sub- 
auratus than in canadensis; that the spine tends to originate at its dorsal ex- 
tremity closer to the coracoid border in fiber and canadensis; the lateral twist of 
the spine in canadensis and the comparatively straight spine in fiber and sub- 
auratus; that the angle of the glenoid and coracoid borders, if produced, is 
greatest in subawratus; that the superior angle is in canadensis more angular. 
[104] 
