SIWALIK MAMMALIA. 
7 
convex instead of concave, and the teeth are of very much larger size. In regard 
to the contour of the maxilla C. anubis comes nearer to the fossil. The length of 
the space occupied by the five cheek-teeth is the same as in a full-sized male of the 
large C. porcarius, but the true molars of the fossil are considerably wider. The 
writer has been unable to compare the fossil with female skulls of all the existing 
species of the genus, but judging from the last comparison it would seem probable 
that the Siwalik form attained a larger size than any existing species ; and this, 
together with the apparent extinction of all the contemporary mammals, indicates 
that there can be little doubt as to its specific distinctness. 
Species 2. Cynocephalus falconeri, n. sp. nobis. 
History. — The history of the type and only known specimen of this smaller 
species is recorded in the u Cat. Foss. Mamm. Brit. Mus.” pt. I. p. 6. 
Mandible. — The type mandible was obtained from the Siwalik Hills, and is 
represented in pi. I. fig. 4, the right ramus of a mandible of a female of G. babouin 
being represented in fig. 5. The fossil comprises the entire symphysis and the 
greater portion of the right ramus, and shows the three true molars in a well-worn 
condition, together with portions of the two premolars ; the canine is wanting, but 
the protuberance of the ramus at the point where this tooth should be, together with 
the generally elongated form of the jaw, indicates that the specimen probably 
belonged to a male. 
That this mandible belongs to Cynocephalus is at once evident from the elon- 
gated symphysis, and the flatness of the oral surface of the latter, 1 together with 
the relatively broad cheek-teeth and the small size of the hind talon of m~3. 
The length of the space occupied by the three true molars is very much less than in 
the palate represented in fig. 3, which at once indicates that the present mandible 
(even if it belong to a female) is specifically distinct from C. subhimalayanus . 2 The 
length of the space occupied by the three true molars is the same as in the female of 
G. babouin, but the length in front of pm. 1 is much greater. 
Specific distinctness. — Although it cannot be certainly affirmed that the present 
form is specifically distinct from all the existing species of the genus, yet the 
apparent extinction of all the true Siwalik mammals renders it probable that this is 
the case, and the name of C. falconeri is accordingly proposed for it. 
II. THE ANTELOPES. 
Genus. OREAS, Desmarest. 3 
Distribution. — The two existing species inhabit all tropical and southern 
Africa. Palceoreas is an allied form occurring in the lower pliocene of Pikermi, in 
1 Semnopithecus and its allies (fig. 6) have the symphysis deeply depressed immediately behind the incisors. 
2 In the Cercopithecida the length of the lower molars always exceeds that of the upper ; compare figs. 5, 2. 
3 “ Mammalogie,” p. 471 (1822). 
