mina which are small. The back of the .skull is more rounded, nar- 

 rower, and proportionally longer than in Antilocapra. From the upper 

 posterior pai"t of the orbit narrow depressions extend backward and 

 unite on the parietal bone half way between the suture which sepa- 

 rates that bone from the frontal, and the inion. At their junction a 

 low ridge representing the sagittal crest begins and extends back to the 

 occupit. The upper posterior portion of the skull is more like that of 

 Oreodon than of the deer, prong buck or sheep. It is much like 

 that of the camel. In Camelus dTomedarius the sagittal crest is more 

 strongly developed, is longer, the downward slope toAvard the 

 occiput is not so sharp; and the inion projects more superiorily and 

 posteriorly. In the region of the inion it is almost like the correspond- 

 ing part of the cat. 



The otic bullae are very large as is also the meatus auditorius ex- 

 ternus. The orbits are also large and extend outward very promin- 

 ently. 



The lower jaw is complete with all the teeth except the canine and 

 the third incisor of the left side. 



The incisors are of nearly the same size and shape, being slightly 

 spatulate or wider on the cutting edge, which is round and sharp. The 

 canine has nearly the same form but is smaller. It joins the third 

 incisor as in modei'n ruminants. The disastema is long and the 

 ramus slim beneath. The foramen mentale is situated about one- 

 fourth the distance from incisor 3 to premolar 2. There is another 

 small foramen just forward of premolar 2. It is a little farther for- 

 ward on the left than on the right side. 



Permanent premolar 2 is just protruding. The other premolar's are 

 of the deciduous set. Temporary premolar 3 is three lobed, as is also 

 premolar 4 which is much longer. 



The molars are prismatic and differ little from those of Anti- 

 locapra. Tbe mandible and inferior dentition differ from Scott's de- 

 scription of Cosoryx fnrcatus * in the following respects. The man- 

 dible is more convex both on the outside and inside than in Antilo- 

 capra making the jaw more robust. The valleys of the molars are 

 proportionally as wide and as long as in that genius. The second in- 

 cisor is slightly the largest. The first molar is as large as the second. 

 The chin is different from Scott's figure, not being at all prominent. 

 The angle is formed by a slight descent beneath the foraman mentale. 

 It then continues forward horizontally until it ascends abruptly be- 

 neath tlie incisors. The foot bones are nearly like those of Blasto- 

 nu'i-yx described by W. B. Scott. ** 



*Bull. Mus. of Comp. Zool. 1800. Vol. XX, No. 3, p. 82. 

 ** 11). page 80. 



