the (?) Pliocene of British East Africa. 417 
(Pithecus). Remains of other extinct baboons are known, 
but in most cases are too imperfect for useful comparison. 
On the whole, it may be asserted that the specimen now 
described represents a new generic type distinguished by 
(1) the shortness of the snout, (2) the relatively large size 
of the cheek-teeth, (3) the great length of the molars in 
proportion to their width. 
The name Simopithecus is proposed for this genus, the 
name of the species being S. oswaldi, The female skull and 
lower jaw described above are to be taken as the type- 
specimens *, 
This comparatively short-snouted form, with its powerful 
dentition, may, perhaps, have been the forerunner of the 
baboons with the elongate muzzles, and in many respects 
resembles the Gelada baboon (Theropithecus gelada) of 
Abyssinia, in which the prolongation of the face is less 
marked than in most species of Papio, especially in the 
males. 
It is unfortunate that the lmb-bones are nearly all in- 
complete, so that their proportions cannot be estimated 
with certainty. Some of the specimens show that some indi- 
viduals of this species attained a very large size. 
The humerus is represented by the distal end of a large 
specimen and the lower three-fourths of a smaller one, both 
from the left side. In the large specimen the flange on the 
ulnar side of the articulation is less produced than in the 
mandrill (Papio sphing) and the male of Theropithecus. 
Otherwise it is very similar to that of the mandrill, espe- 
cially in the strong development of the internal condyle. 
The width of the distal articulation in the fossil is 84 mm. ; 
in a large mandrill with a humerus 222 mm. long the width 
is 33 mm.; in the male Theropithecus it is 23 mm. The 
form of the distal end of the smaller humerus is almost 
exactly as in the male Theropithecus, but, judging from the 
ridges on the shaft, the bone was considerably shorter and 
* A brief account of a number of mammalian remains from Central 
Africa has lately been given by Hans Reck (Sitzungsb. Gesellsch. 
Naturforsch. Freunde Berlin, nos. 3 & 7, 1914). These specimens are 
from beds, probably of Pliocene age, exposed on the sides of a gorge 
cutting into the edge of the Serengeti Plateau at Oldoway (lat. 3°S., 
long. 35° 25' E.). Among the more important discoveries are two 
species of elephant, one apparently very similar to, if not identical with, 
that from Homa Mountain, a baboon which may be the same as that 
now described, a three-toed horse near Hipparion, and, lastly, a nearly 
complete human skeleton which Reck regarded as contemporary with 
the other remains, though this seems to be at least doubtful. 
