12 
INDIAN TERTIARY AND POST-TERTIARY VERTEBRATA. 
being represented of the full size in fig. 3 of the same plate. The specimen has lost 
its two extremities, the crowns of the cheek-teeth of the right side, and the outer 
walls of some of those of the opjDOsite side, but is otherwise in excellent 
preservation ; many of the cranal sutures being distinctly visible. The condition 
of the teeth shows that the skull belonged to a fully adult, though not an old 
individual. 
The grinding surfaces of the teeth cannot be completely cleaned from matrix ; 
although this has been accomplished sufficiently to exhibit the complete isolation of 
the anterior pillar (e),^ characteristic of Rippotlieriiim ; as well as the com 2 fiex 
plication of the dentine and enamel in the central part of the crown, which is 
especially well-marked in both the Indian species described in the second volume. 
The anterior pillar [e) is less prominent and less elongated in cross-section than in 
the teeth of H. theohaldi figured in the same volume^ ; while the posterior pillar (/) 
is not constricted at its junction with the inner column, as is the case in little- worn 
teeth of that species,'^ and is larger than in well-worn teeth of the same.'^ In all 
these respects the teeth of the Perim skull agree with those of II. antilqpinnnv’ ; as 
well as with the isolated tooth from the Punjab of which a polished transverse 
section is rej^resented in plate III., fig. I, of this volume. In the following table 
the dimensions of the Perim skull are compared with those of the three maxillae 
referred to II. antilopinum in the second volume® ; viz. 
Previous specimens. 
Perim skuU. 
Width of palate po.steriorly 
( 
2*0 
2-8 
,, between pm. 4 . . . . 
1-9 
2-6 
Length of 
series of cheek-teeth ..... 
5-3 
5-8 
n 5> 
three true molars 
2-36 
2-5 
2-67 
>> 
pm. 2 
1-25 
1-25 
Width ,, 
0-83 
Length ,, 
„ 3 
0-96 
0-96 
0-96 
Width „ 
. • • • . . . . 
0-95 
0-9o 
1-04 
Length ,, 
„ 4 
0-93 
0-9 
0-9 
0-92 
Width „ 
• • • • • • 
0-86 
0-91 
0-9 
Length ,, 
m. 1 . 
0-8 
0-81 
0-8 
0-88 
Width ,, 
j, . , . . . . 
0-85 
0-88 
0-9 
Length ,, 
„ 2 
0-85 
0-82 
0-8 
0-87 
Width ,, 
, , , , . . • 
0-70 
0-72 
0-85 
0-93 
Length ,, 
„ 3 
0-8 
0-85 
0-98 
Width „ 
mm* * * * • • • 
0-55 
0-75 
0-83 
It will be observed that the teeth and palate of the Perim skull 
are somewhat larger 
than those of 
either of the other specimens. 
although 
the teeth 
are still considerably 
smaller than 
those of H. theohaldi figured 
in the second volume. It will also be 
observed that 
in the Perim skull the leno:th of pm. 3 is 
less than its width. 
the reverse 
being the case in the other three specimens. Analogous differences prevail, however, 
in the latter, since the length of pm. 4 of the specimen in the first column exceeds its 
width, the reverse prevailing in the other two specimens ; these differences need not, 
1 For the terms employed in the description of the cheek-teeth of the horses, see vol. II., p. 73. 
2 Plate XI., fig. 3. 3 ILicK 4 Vol. II., pi. XIII., fig. 2. 
5 Ibid., pi. XI., fig. 1. “ F.A-S.,” pi. LXXXIII., fig. 18. 6 Page 76. 
