161—74 CEANIA OF RUMINANTS FROM THE INDIAN TERTIARIES. 
above the orbits ; these horn-cores were directed upwards and outwards ; their com- 
mon base was constricted at its origin : the frontals were laterally contracted above 
the orbits, and the face presented a slightly convex profile : the molar teeth want the 
crenulated folding of the enamel of the inner semi- circle of the islands found in 
the teeth of Sivatherium, and have a minute accessory tubercle in the valley dividing 
the inner sides of the two barrels. 
To return to our own specimen. We find that the cranium itself is almost com- 
plete, though the horn-cores have been broken off at their base ; the extremities of 
the nasals, maxiUse, and premaxillse are also wanting. The crowns of the first pre- 
molars have been broken off at then’ bases. 
The cranium is that of a fully adult animal, most of the cranial sutures having 
become obliterated, and the molar teeth being about one-third worn down. Like 
the crania of the allied genera, the present specimen is remarkable for its general 
massiveness and bulk : at the line of fracture the frontals are produced into an 
enormous mass of bony structure, which formed a common base for one or more 
pairs of horn-cores ; this base measures as much as thirty-four inches in circumfer- 
ence ; the profile of the face is very markedly concave, with an obtuse re-entering 
angle at the junction of the frontals and nasals ; there are no horns immediately 
over the orbits. The orbit, as in the allied genera, is placed very low down on the 
skull, far removed from the plane of the face ; its antero-posterior diameter is longer 
than its transverse diameter, and its central axis is directed outwards and forwards, 
so that its zygomatic border is considerably more prominent than its frontal border ; 
a complete bony ring surrounds the orbit, which is small in comparison to the size of 
the cranium. The nasals are short and straight, extending as far upwards as the lower 
border of the orbit; they seem to have been narrower than those of Sivathermm, and 
have no trace of the arching found in those of that genus ; in the specimen the greater 
part of the nasals are broken away, but a cast of their inner surface remains ; from 
this fracture and from the obliteration of the cranial sutures, it is not easy to determine 
the precise relations of the nasals to the surrounding bones ; it seems, however, to be 
quite clear that the nasals articulated with the maxillse, though probably not with 
the premaxillae. There does not seem to be any resemblance in the form of the nasals 
and frontals to those of Saiga, with which Dr. Mmle* has sought to affiliate Siva- 
therium, chiefly on account of the form and relations of the nasals : in the present 
cranium the anterior nasal orifice is comparatively small, and bears no resemblance 
to the enormous orifice of Saiga, neither do the nasals reach to the median line of 
the orbits as in the latter genus, but, on the contrary, are completely below the orbits. 
The superior surface of the nasals forms an obtuse angle with the frontal plane ; this 
angle is larger than in Sivatherium ; the anterior nasal orifice presents an approxi- 
mately circular transverse section, the transverse diameter being rather the larger of 
the two ; the foramen for the maxillary branch of the fifth nerve is of rather large 
‘ Geol. Mag., Yol. VIII, p. 44. 
