16 
MOLAR TEETH AND OTHER REMAINS OE MAMMALIA. 
The antero-external angle of the tooth forms a small, sharp, wedge-shaped 
process ; there is one prominent costa on the dorsum of the tooth near this angle ; 
it is not continued upwards as far as the neck. Unfortunately the postero-external 
angle of the tooth is broken away, so that it is impossible to determine the form of 
this portion of the crown : from an examination of the base of the crown, where 
it is buried in the matrix, I consider that the whole of the outer side of the 
tooth was nearly parallel to the inner side ; and that the antero-posterior angle was 
not produced. The dimensions of this specimen are — 
In. 
External side 
... 2-0 
Internal side 
... 1-3 
Anterior side 
... 2-0 
Posterior side 
... 1-5 
The molars of both Rhinoceros jplatyrhiniis and R. namadicus are distin- 
guished from those of R. sivalensis and R. palceindicus by the complex form of 
the crochet, and by the presence of a comhing-plate. The points by which the 
molars of the present species are distinguished from those of R. platyrhinus are 
the following : — 
Difference in form of the median valley and the base of the two codes. 
Presence of an antecrochet. 
Difference in size of combing'-plates. 
Greater size of anterior valley and cingulum. 
Relations of posterior valley to median eollis, and its relative size. 
Smaller size. 
The other specimen figured {plate 6) is the entire and perfect germ of a 
third or .ultimate molar of the left maxilla from the Nerhudda valley ; the specimen 
is in the Indian Museum. I refer the specimen to the same species as the preceding. 
The figure is taken from the postero-internal aspect of the specimen, looking dhectly 
into the median valley ; the anterior eollis occupying the left side of the valley and 
the median eollis the right. 
The anterior eollis forms by far the greater extent of the base of the tooth ; 
its transverse section has the form of an isosceles triangle ; the summit is bent 
over towards the inner side ; on the anterior side the cingulum commences on the 
external edge, and forms a V-shaped line along this side of the tooth, running as 
far as the base of the anterior eollis ; close to the anterior eollis there is a narrow 
anterior valley of triangular form {seen on the extreme left of the figure) ; the lowest 
point of the cingulum is rather more than half an inch above the neck of the 
crown. The median vaUey is entered by a low pass, without any tubercle at the 
entrance ; this valley becomes deeper as it passes outwards ; the level of the pass 
is the same as that of the cingulum ; the entrance of the valley is wedge-shaped. 
The crochet {the first projection across the valley) is of great size and extends com- 
( 34 ) 
