109—22 CEAXIA OP EUMINANTS PEOM THE INDIAN TEETIAEIES. 
Bos PLANiFRONS, n. sp. nohis. PI. 12, f. 2 ; PL 16, f. 4. 
The specimen figured in the above-mentioned plates consists of an upper 
part of the frontlet with the greater part of the horn-cores of a species of Bos 
distinct from the last species ; the specimen was collected in the Siwaliks of the 
Punjab by Mr. Theobald. On referring to the table of measm^ements on page 66, 
it will be seen that the antero-posterior diameter of the forehead of this species is 
longer than the transverse diameter, while if we turn to the view of the occipital 
surface {Blate XVI, fig. 4), we shall see that the horn-cores are placed upon an ele- 
vated ridge immediately over the occiput, that there is no distinct parietal band across 
the back of the cranium, and that the frontals are nearly flat ; the transverse section 
of the horn-cores is somewhat eUiptical, and the occiput is squared and but slightly 
indented laterally by the terminations of the temporal fossse. All the above charac- 
ters clearly show that the specimen should be referred to the restricted genus Bos, 
although the elliptical cross section of the horn-cores differs from type species 
of that group. 
The above characters also sufficiently distinguish our specimen from the living 
genus Bibos ; the direction of the horn-cores sufficiently distinguishes it from 
Bos namadicus, since in the present specimen the horn-cores are directed almost 
immediately outwards, with a slight tendency upwards and inwards, and they do not 
curve forward as in Bos nmiadictis. In the latter species the tips of the horn-cores 
of the figured specimen are about two feet in advance "of the plane of the frontals, 
whereas in B. 'plcmifirons the horn- cores where broken are not more than three 
inches in advance of the same plane. The occipital surfaces of the two type forms 
are also slightly different, that of the Siwalik species being more strictly Taurine. 
As is shown in the figure of the forehead, the frontals are longitudinally 
fissured in our specimen, the parts on each side of the line of fracture being 
somewhat laterally compressed, so that the median line of the frontals is tlirown 
forwards in advance of its proper plane, thereby causing the forehead to appear 
more convex than it naturally would be. In the unbroken condition of the 
frontals these bones would be very nearly flat between the horn-cores ; below the 
bases of the horn- cores, the median line of the frontals becomes somewhat more 
prominent, and the lateral surfaces slope away on either side, so that the anterior 
border of the orbit is plaeed somewhat below or behind the median line of the 
frontals. The lateral surfaces of the frontals are marked by supra-orbital sulci 
of great width and depth, which converge together as they descend : there are no 
distinct supra-orbital foramina in the specimen ; this is, however, probably only an 
individual peculiarity. The lateral contraction of the forehead between the base of 
the horn-core and the orbit is distinct, though of no great length ; the re-entering 
angle for the insertion of the apex of the nasals is seen on the lower border of the 
figure ; it does not extend upwards as far as the centre of the orbits. 
