33 
MOLAR TEETH AND OTHER REMAINS OE MAMMALIA. 
Genus Acerotherium, Kaup . 
Of this genus we have one species in India ; the species is only known by its 
molar teeth, which correspond in general form with those of the Miocene European 
species, but we have no means of knowing whether the Indian form was hornless, or 
whether the number of its digits were similar to those of the European genus. 
Acerotherium Perimense, Ealconer. Flate 6, Figs. 2 and 5. 
The specimen drawn in figure 6 is a portion of a left maxilla from the collec- 
tion of the Asiatic Society of Bengal, which was obtained in Perim Island in the 
Gulf of Cambay; it contains the last premolar and the first molar teeth. The 
other specimen in the same plate ( Fig. 2 ) is a first molar of the left maxilla ; this 
specimen with two others was collected by Mr. Theobald in the Siwaliks of the 
Punjab. These are the first recorded specimens from that formation. The Siwalik 
specimen is less worn than those from Perim Island, but the two agree precisely in 
size and form. 
The molars of this species are distinguished from those of Rhinoceros by their 
transverse diameter exceeding their antero-posterior in length. The median collis 
( right side of figures ) is slightly larger than the anterior collis ( left side of figures) . 
A cingulum surrounds the whole of the inner half of the crown and is lowest on 
the inner face. The median valley {middle of lower border of figures) is entered by 
a high pass. The bases of the colles are in contact at the pass. A small and blunt 
crochet is seen in Eigure 2. In the Perim Island specimens this has become oblite- 
rated by wear ; the direction of the upper portion of the valley is different from that 
of the bottom, so that the valley in the two specimens have contrary directions. 
A very small enamel island would be formed on the crown were the tooth worn down 
to the level of the cingulum. The posterior valley {on the right side of the figures) 
is small and oval ; the inner wall slopes rapidly. The antero-external angle if eft top 
angle of figures ) forms a small buttress with two costae ; this angle is more bevelled 
away in the specimen drawn in Eigure 2 than in the specimen drawn in Eigure 5. 
The measurements of the Perim Island molar are — 
In. 
External side 
Anterior side 
Internal side 
Posterior side 
1- 5 
2- 5 
1- 4 
2 - 8 
The premolar is less worn than the molar, and is almost square in shape. The 
cingulum has been partly broken away along the inner side. Its measurements are — 
External side 
Anterior side 
Internal side 
Posterior side 
. 1-5 
. 1-4 
. 1-2 
. 1-4 
( 31 ) 
