No. 2.] THE RELATIONS OF PROTOCERAS. 315 



The frontals are large, though less extended antero-pos- 

 teriorly than in the modern Pecora and forming less of the roof 

 of the cerebral fossa ; they reach from a little behind the orbits 

 to considerably in front of them, but the temporal ridges do 

 not encroach upon them at all. They are transversely concave 

 and at their outer edges are raised and thickened to form the 

 rugose upper borders of the very prominent orbits. Though 

 far less so than in the males, these projections are much more 

 striking than in the recent Pecora. In the median line of the 

 frontals not far from the parietal suture is a small, rounded 

 and more or less rugose eminence, which varies in size in the 

 different individuals, though it is not prominent in any of the 

 females which I have seen. Judging from Marsh's figures and 

 description, it would appear to be better developed in the type 

 specimen. As in the oreodonts and primitive artiodactyls 

 generally, the supraorbital foramina are placed near to the 

 median line and the vascular grooves which run forward from 

 them are very distinctly marked. There is a small frontal 

 sinus. 



The nasals are very remarkable ; they are broad from side 

 to side, but exceedingly short. The median portion is elevated, 

 transversely convex, and projects slightly beyond the maxillary 

 suture, the free portion rapidly tapering to a point. The lateral 

 portion is more depressed and flattened and unites suturally 

 with the maxillary, frontal and lachrymal. Owing to their 

 extreme shortness, they are, of course, very far removed from 

 any contact with the premaxillaries. Though the reduction of 

 the nasals is less extreme than in the saiga antelope, this part 

 of the skull has a striking resemblance to that animal, and as 

 in it, the nasal chamber has no osseous covering for nearly the 

 whole of its length. It can hardly be doubted that Protoceras 

 must have possessed a proboscidiform muzzle much like that 

 of the saiga, and as in that genus, the turbinal bones were 

 doubtless greatly shortened. In the moose {Alces) the nasals 

 and turbinals are considerably reduced in length, though to a 

 much less extreme degree. 



The edentulous premaxillaries are very much like those of 

 the modern ruminants, except that they are of unusually small 



