18 
MOLAR TEETH AND OTHER REMAINS OF MAMMALIA. 
specimen is considerably more ‘‘ bysodont” tban that of tbe last molar of uni- 
cornisy being absolutely higher and also narrower at the base. 
It is to be hoped that eventually the skull of this species will he obtained from 
the Nerbudda valley, that we may have more complete evidence as to the distinct- 
ness of the species. The lower molars are unknown. 
Rhinoceros iravadicus, n. sr. nobis. Plate 5, figs. 1 and 2. 
The species is founded on two upper molars from the mammaliferous strata of 
Ava {plate 5, Hgs. 1, 2) ; both specimens are in the Indian Museum. 
The most worn of the two molars {fig. 1) was discovered in a pagoda at Prome, 
and presented to the Indian Museum by Colonel Phayre ; from its mineral condi- 
tion there can be no doubt but that it is derived from the bone beds of the Irawadi 
valley. The crown is complete, with the exception of a small triangular piece of 
enamel chipped from the outer wall ; the “ fangs” have been broken off close to 
the neck. The tooth has been in wear for a considerable period, the height of the 
anterior collis above the neck being only *9 inch. The specimen is from the left 
maxilla ; and from its large size and elongated shape is probably the penultimate 
true molar. This is the specimen referred to by Mr. Foote in his Memoir on R. 
deccanensis, in the first part of this volume (p. 16). 
The anterior collis {on the left side of the figure) is of much greater size than 
the median {on the right side of the figure), occupying nearly one-half of the in- 
ternal face of the tooth ; on its inner side it slopes away slightly from its base 
downwards to the outer side ; on its posterior side, it gives off a blunted antecro- 
chet, projecting into the median valley {the centre of the figure) internally to the 
crochet. The anterior surface of the tooth has a projecting angle {the centre of the 
left border of the figure) in the middle of its course; the cingulum commences 
at this angle, and is continued as a distinct ledge up to the antero-internal angle 
of the tooth ; there is a very small and shallow anterior valley between the cin- 
gulum and the anterior collis ; along the internal surface of the anterior collis the 
cingulum may he traced as a slight wavy line on the enamel, and as a still fainter 
line on the median collis. 
The entrance to the median valley is blocked by a large ovate tubercle, ver- 
tically grooved on its internal surface ; this tubercle is continued outwards along 
the bottom of the median valley as a rounded ridge. The median valley runs, 
from its commencement, forwards and outwards, becoming deeper as it advances ; 
it is of great width throughout its extent ; its transverse diameter at the entrance 
is *4 inch, and at its narrowest part, caused by tbe projection of the crochet, 
“2 inch; throughout its length it preserves a considerable width along the bottom; 
the bases of the colles being nowhere contiguous. 
The walls of the median collis are more abrupt than those of the anterior ; 
the crochet is short and blunt, not projecting more than half way across the valley; 
( 36 ) 
