Description of the Wild Ass of Tibet. 471 



animal possesses most of the essential characters of that sub- 

 genus. The scull, as compared with that of the horse and 

 mule, (I have no ass* scull wherewith to compare it) offers 

 some striking peculiarities. In the first place, the dental 

 formula is anomalous, exhibiting two extra molars which 

 are small, ovoid, simple, and placed in front of the usual 

 series. 



fi 11 7 7 



In the Kiang the dental formula is as follows : ^ yr -^ 

 Total 42. 



In the Kiang moreover, the scull is more massive and 

 weighty, exhibiting throughout more height as well as breadth, 

 and its superior and inferior outlines are much less recti- 

 linear; the rami of the lower jaw being much bent up towards 

 the junction of the incisors, and the frontal and nasal bones 

 being nearly as much bent down. The condyles of the lower 

 jaw are less elevated, and the ascent to them from the posteal 

 part of the rami is by straighter lines. The nasal, maxillary, 

 malar, frontal, and parietal bones, have greater development ; 

 so that the senses, as well as the intelligence of the Kiang, 

 ought to be quicker than those of the horse or mule. The 

 encephalon is decidedly more capacious, and so is the nasal 

 cavity in the Kiang. The frontals, both lengthwise and 

 across, are more arched. And the nasals have a longitudinal 

 groove along the mesial line. The zygomatic arches are 

 shorter and differently curved : the orbits are fully as large 

 or larger. The great foramen and its condyles are carried 

 less far backwards, so that instead of forming the most 

 posteal part of the scull (as in the horse and mule), they fall 

 considerably within the perpendicular of the transverse or 

 occipital crista. The incisors of both jaws are nearly erect 

 in the Kiang, instead of sloping forwards or outwards as in 

 the horse and mule ; and lastly, the scull of the Kiang is much 

 more suddenly attenuated towards the front or base of the 

 incisors, where the breadth of the scull does not exceed that 

 of the horse's scull. 



