NEW RUMINANTS FROM THE SIWALIKS. 
11—115 
cores to the orbits. The first notice of the occurrence of a species of this genus in 
the Siwaliks is in the first volume’ of tlie present work, where some teeth and jaws 
are briefly mentioned under the name of Portax. In a subsequent notice^ a fore-limb 
from the Siwaliks of the Punjab was also referred to the same genus ; but no specific 
name was assigned in either case. 
Upper dentition. — In plate XIII., fig. 1, there is represented the masticating and 
inner aspect of the cheek-teeth of the left maxilla of a ruminant collected by Mr. 
Theobald in the Siwaliks of the Punjab. The specimen belonged to a young 
individual and shows the three milk-molars (mm. 2, mm. 3, mm. 4) in a well-worn 
condition, and the first and second true molars (mm. 1, mm. 2) in an early condition 
of wear, and not fully protruded. In figure 2 there is represented the external 
aspect of the teeth of a precisely similar left maxilla, from the same locality, con- 
taining mm. 3 , mm. 4, and m^ . 
It will suffice to say that the teeth of these specimens correspond so exactly 
with the homologous teeth of a young female individual of Boselaphus tragocamelus 
that there can be little hesitation in referring them to the same genus. ^ The only 
difference that can be detected between the recent and fossil teeth is that the latter 
are of considerably larger size, and that the central enamel-pits of the true molars 
are less deep, while the hinder wall of the posterior ‘ crescent ’ of m. 2 is somewhat 
lower, thus causing the union of the dentine surface of this ‘ crescent ’ with that of 
the corresponding ’ lobe ’ to be somewhat later. The lesser depth of the middle 
enamel-pits causes the lip of the ‘ crescents ’ of the fossil teeth to be thicker than in 
those of the living species. In the following table the dimensions of the fossil teeth 
are compared with those of the above-mentioned skull of B. tragocamelus., viz .\ — 
Length of five teeth 
) > 
> > 
,, mm. 2 
)> )> 3 
,, .. 4 
,, m. I 
Fossil. B. tragocamelus. 
4-65 
3-73 
0-83 
0-67 
0-92 
0-94 
0-78 
0-9 
0-92 
0-72 
IT 
Ml 
0-97 
1T9 
1-05 
In figure 7 of the same plate there is represented a well-worn left upper true 
molar, from the Siwaliks of the Punjab, in which the greater part of the accessory 
column in the median valley has been broken away. The tooth of which two views 
are given in figures 8, 11 of the same plate is an almost unworn right upper true 
molar, from the same locality. In this specimen, as in m, 1 of fig. 2, the first costa 
of the anterior crescent is less strongly developed than in the true molars of fig. 1 ; 
but it is probable that this difference is merely of individual value. 
Loiver de^itition. — In plate XIII., fig. 5, there is represented a fragment of the 
left ramus of the mandible of a large ruminant, collected by Mr. Theobald in the 
Siwaliks, which from its size and the resemblance of its teeth to those of the nilgai 
1 Page XV. (1880). 2 “ Records,” vol. XVI., p. 76. 
3 The molars of Uippotragus are very similar to those of Boselaphus, hut have the borders of their outer surfaces more 
nearly parallel. 
