26 
MOLAR TEETH AND OTHER REMAINS OE MAMMALIA. 
The presence of the surrounding cingulum and the position of the pass into 
the median valley sufficiently distinguish it from Ealconer’s three species of Siwalik 
Rhinoceros, and from the Nerbudda and Burmese species. 
The only one of the above noticed species with which I think the present 
specimen can have the least affinity is R. planidens of the Siwaliks. The general 
form of the cingulum is, however, very different in the two : in the present specimen 
this continues in a straight line along the whole of the anterior surface, whereas in 
R. planidens it bends to form a distinct anterior valley, and does not extend more 
than half-way across the anterior surface of the tooth ; the cingulum, moreover, in 
the latter species does not extend completely across the inner surface of the median 
coHis, as in the present specimen. 
The greatest difference, however, is found at the entrance to the median valley 
in the two specimens : in R. planidens, the cingulum forms a distinct tubercle at 
the entrance to the median valley, and the top of this tubercle becomes the pass 
into the valley, there being no contact of the base of the collis further in. 
These differences are so great that I do not think the two specimens can belong 
to the same species : at the same time it is not quite impossible, as considerable 
variations do sometimes occur between the molar and premolar series of the same 
species. 
The only described species of Rhinoceros with which this specimen agrees at all 
closely is R. deccanensis of Mr. Eoote. The premolars of that species {plate 1 of 
the first part of this volume) are of exactly the same general form and type as the 
present specimen. They both have a complete cingulum, are of the same size, and 
have the same internal pass between the colles into the median valley. The main 
differences I can detect between the two are the following : in R. deccanensis the 
cingulum forms a more complete collar round the crown, it makes a distinct ledge 
on the inner surface of the median collis, instead of only a waving line ; while on 
the anterior surface it is raised up into'a sharp edge on its free border, and so 
forms an anterior valley, instead of a flat ledge. The pass between the colles is still 
further away from the cingullum in the present specimen than in R. deccanensis ; 
and in the latter there is not the vertical groove on the antero-internal surface of 
the anterior collis. Eurther, the lowest part of the cingulum in the premolars of R. 
deccanensis is opposite to the pass between the two colles ; the cingulum rises con- 
tinuously on either side from this lowest part ; on the anterior surface the cingulum 
is higher than on any part of the internal surface of the anterior collis. In the 
present specimen the cingulum has its lowest level along the anterior surface ; the 
portion on the internal surface of the anterior collis is higher than that on the 
anterior surface. 
I hope that further specimens will subsequently be acquired which will further 
elucidate the affinites of this specimen ; for the present I think that it is probably 
a distinct species. Its relationship with the Deccan Rhinoceros, the two separated 
far in time and space, is very interesting, as I pointed out in my papers on tertiary 
( 41 ) 
