16 



[February, 1844. 



all the proportions of the head, as the subjoined drawings will 

 show. 



In the H. minor there is a uniform convexity of the upper sur- 

 face of the cranium, from orbit to orbit, and between the occiput 

 and ossa nasi ; while in the common species the orbits are re- 

 markably elevated, and the intermediate surface is concave. The 

 orbit is placed about midway between the occiput and snout, and 

 the latter is consequently short ; while in the large species the orbits 

 are placed about one-third the distance between the occiput and 

 snout. The H. minor has only two canines in the lower jaw ; 

 the false molars are proximate to the canines ; and the base of 

 the zygoma? is in the same plane with the upper maxilla. 



The second skull of this species (which is of the same length 

 as the other) is that of a younger animal ; for the sutures are 

 open, and the teeth in the process of changing from the deciduous 

 to the permanent set. The posterior molars are only partially 



