3§4 



CLASS MAMMALIA. 



and the upper true molars and the hinder premolars bearing two 

 main oblique ridges, which usually form one or two Vs. Upper 

 and lower canines are always present. The pelvis (as seen in fig. 

 1260) resembles that of the Elephants in the enormous expansion 

 and vertical position of the ilia, but is distinguished by the circum- 

 stances that the ischia do not enter into the ventral symphysis. 

 This suborder is usually divided into three sections ; but a form 



Fig. 1257. — Outline of upper aspect of cranium (a), the left manus ( B 1 ) and pes (c) of Corypho- 

 ■doii hamatus; from the Wasatch Eocene of North America, a, one-fifth, b and c, one-third 

 natural size. 



recently discovered in the Bridger Eocene of North America, and 

 named Elachoceros, presents characters connecting the last two, and 

 will perhaps render it eventually necessary that they should be 

 abolished. Excluding this form, the characters of the three sections 

 are as follows : — 



1 In the first row of carpal bones the one on the right of the figure is the 

 cuneiform, the central one the lunar, and that on the left the scaphoid ; in the 

 second or lowest row the bone on the right is the unciform, the central one the 

 magnum, and the one on the left the trapezoid. 



