MOLAR TEETH AND OTHER REMAINS OE MAMMALIA. 
29 
bably the first, or perhaps second (the first disappearing), of the premolar series. 
The anterior wall of a larger succeeding tooth is seen on the left side of the figure. 
The specimen is quite complete ; it had only just come into use, the tip of the 
anterior collis and the anterior part of the external wall being the only portions 
flattened by abrasion. 
The tooth is remarkable for the excessive prolongation of the antero-external 
angle {the angle on the right of the figure) in a manner unlike that of any other 
recent or fossil form that I have seen. > Erom the presence of a combing-plate the 
tooth belongs to the type of B. platyrhinus and R, namadicus ; but differs entirely 
in form from the premolars of the first of these species, which, as shown in Colonel 
Baker’s cranium, are nearly square. 
The dorsum has three costae, one at the posterior angle {left of figure) and two 
others placed at equal distances in advance of this, the anterior one occupying the 
middle of the dorsum; from this anterior costa the dorsum slopes a’way to the 
antero-external angle. The anterior collis on the right of the figure is very small, 
with a concave border towards the median valley ; the dentine surface proceeding 
from this collis towards the outer wall of the tooth runs obliquely forwards so as to 
be almost parallel with the posterior half of the outer wall. 
The median collis {on the left of the figure) is larger than the anterior; it 
gives off a long sinuous crochet, stretching far into the median valley : from the 
external wall of the tooth there are two long and slender combing-plates, parallel 
to one another; the posterior of these unites with the extremity of the crochet, 
while the anterior joins the anterior crochet ; a third small process occupies the 
angle between the posterior combing-plate and the outer wall. 
The median valley is entered by a low pass, without any tubercle at the 
entrance ; it extends far up towards the antero-external angle of the tooth, and 
is of larger extent than in any other described tooth. 
Along the anterior side there is a wavy cingulum, but little raised from the 
surface ; there is no distinct anterior valley. The posterior valley is large and 
nearly circular, entered by a high and narrow pass. 
The measurements of this specimen are — 
la. 
External side 
... 1-6 
Internal side... 
... 0-6 
Anterior side . . 
... 1-4 
Posterior side 
... 1-3 
The specimen differs from the preceding Burmese specimens by the greater 
production of the antero-external angle, by the small size of the anterior collis in 
proportion to the median, by the double combing-plates, and by the slighter 
cingulum, and by the absence of the anterior valley. It belongs to the hypsodont 
type, though tending towards the brachydont. The only species to which it could 
possibly belong is Rhinoceros namadicus ; and until a larger series of the molars 
( 47 ) 
