160 



CASTOR. 



Measurements. Total length, 1070; tail vertebrae, 360; scaly por- 

 tion of tail 290X125; hind foot, 185. Skull: occipito-nasal length, 

 134; Hensel, 122; zygomatic width, 97; interorbital constriction, 22 



FIG. 30. CASTOR c. FRONDATOR. 

 No. 35883 U. S. Nat. Mus. Coll. Type. 



palatal length, 78; length of nasals, 46; length of upper molar series, 

 32; length of mandible, angle to alveolus of incisors, 96; height at 

 condyle, 22; at coronoid process, 52. 



