2 
INDIAN TERTIARY AND POST-TERTIARY VERTEBRATA. 
Oeder : UNGULATA.i Sub-Order : PERISSODACTYLA. 
Family : RHINO CEROTIDjH. 
Genus: ACERATHERIUM, Kaup. 
Species : Aceratherium blanfordi, n. sp., nobis. 
Ilistorij. — In the preceding volume of this work a much battered left maxilla of 
a small rhinoceros from the Siwaliks of the Punjab, containing pm. 4 , m. I , and m.^^ 
is figured'^ and briefly described.^ It was there pointed out that the sjiecimen 
apparently came nearest to R. loalceindicus, among the Siwalik rhinoceroses ; and that 
if not the same, it indicated a new Siwalik species : it Avas, however, added that 
there did not seem any evidence at present to Avarrant us in separating the two,” 
and the Punjab specimen Avas, therefore, provisionally referred to R. 'palcoindicus. 
The evidence for the specific distinctness of the form to AA''hich this imperfect 
specimen belonged has been afforded by the more perfect specimens forming the 
subject of the present notice.^ 
Upper molars of larger race . — In plate I., fig. 1, there are represented the three 
left upper true molars of a rhinoceros from Dera Biigti ; in Avhich the Avell-Avorn 
condition of the masticating surface indicates that they belonged to a fully adult 
animal : the first and third teeth are somewhat damaged, but the middle tooth is 
perfect. 
The latter tooth (of Avhich another specimen from Gandoi, in a less worn 
condition, is represented in fig. 2 of the same jdate) is characterized by the 
comparatively small development of the buttress^ at the antero-external angle; so 
that the second costa (c) jDrojects but slightl}^ above the plane of the external surface 
[dorsum) of the croAvn ; while the external surface of the first costa [d) is placed 
very nearly in the same plane. Behind the second costa the dorsum is distinctly 
concave, especially near the free edge, but this concavity is much less marked than 
in many species.® The crown is worn into an irregular concaAuty, as in most 
rhinoceroses. The anterior collis (a) is relatively large ; and at a short distance 
from its inner extremity is constricted by a deep groove on either side. On the 
outer side of the hindmost of these grooA^es there is a bold ante-crochet (/), 2Arojecting 
into the median valley ; the bottom of Avhich is thus comjiletely obstructed in the 
middle. Externally to this obstruction the median valley again exjiands and 
deejDens ; the form of the terminal jiortion being rounded in all early stages of AA^ear. 
1 In accordance with the classification recently proposed hy Prof. Flower (‘ Fro. Zool. Soc.,’ 1883, pp. 184-5) the 
Prohoscidia will be reckoned as a suh-order of the Ungulata. 
2 Plate VI., fig. 1. 3 Pages 44-45. 
i These specimens have been hriefl)^ noticed in the “Records” (vol. XVI., p. 72), when it was thought the mandible 
resembled that of the African species, which turns out not to he the case. 
5 For these terms see vol. II., p. 8. 3 This concavity is most marked in the specimen represented in fig. 2. 
