MOLAR TEETH AND OTHER REMAINS OE MAMMALIA. 
13 
The persistent dentition of this species is as follows - 
y 0“ 0 ip) 0 0 
' 2 ^ " 0 = 0 ' 
P. ^ M. 
3-3 
3-3 
The median lower incisors were very small and functionless ; the first upper 
premolar was shed before the last molar pierced the gum. Falconer compared the 
upper molars of this species to those of Rhinoceros tichorhinus of Cuvier : the molars 
of the two species agree in presenting three fossettes on the crown-surface | hut the 
molars of the European species are distinguished by the greater size of the posterior 
valley, by the non-prolongation of the postero-external angle of the crown, 
by the combing-plate being placed nearly at right angles to the external border, 
by the absence of the cingulum on the anterior surface, and by the dentine-surface 
of the anterior collis being curved instead of straight. The presence of three 
fossettes on the worn-crown sufficiently distinguishes the upper molars of Rhinoceros 
platyrhinus from those of R. hemitcechus, R. leptorhinus, and R. etruscm of Falconer. 
From the molars of both the preceding Siwalik species, the presence of the 
combing-plates in the molars of this species is a sufficient distinction. 
The upper molars of R. platyrhinus agree with those of the living R. indicus 
by having a combing-plate and three fossettes on the worn crown-surface ; those of 
the latter species are, however, distinguished by the non-development of the postero- 
external angle, and by the curvature of the dentine surface of the anterior collis, 
together with the absence of the cingulum on the anterior surface. Irrespective of 
the upper molars the two species are at once distinguished by R. indicus having 
but one nasal horn, while R, platyrhinus had two ; both species agree in having 
a somewhat spatulate mandible provided with large outer incisors. 
The upper molars of R. sumatrensis and R. jamnicus are distinguished from 
those of the present species by having only two fossettes on the worn-crown, and by 
the absence of a combing-plate. 
To show the form of the lower molars of this species I have figured a 
detached premolar of the right ramus of the mandible. The specimen is but little 
worn down, and corresponds in size with the last premolar of the mandible of this 
species figured in the “ Fauna Antiqua Sivalensis ” {plate 76, fig. 10). The anterior 
collis ( extreme left of figure ) is very narrow, and extends as far inwards as the other 
two. The anterior valley ( left of figure ) is noticeable for its very small size and 
narrowness ; the posterior valley, on the other hand, is very large and deep ; the 
anterior valley would be therefore obliterated at an early stage of wear, while the 
posterior would remain for a much longer period. The difference in the times of 
disappearance of the two valleys is greater than in the lower molars of R. sivalensis. 
The worn dentine-surface of the posterior collis ( right of figure ) is placed at right 
angles to the long axis of the crown ; the dentine-surfaces of the other two colies 
are also nearly at right angles to the same axis. There is a distinct cingulum 
running upwards and backwards from the entrance of the posterior valley along the 
1 31 ) 
