SIWALIK RHINOCEROTIDiE. 
55 
teeth were placed behind the symphysis, and accordingly this jaw would seem to 
belong to a distinct species from the other specimen with similar teeth figured by 
the same writers. Hence it would appear that the presence of the isolated pillar in 
the posterior crescent may appear in the lower milk-molars of more than one species 
and that it cannot be regarded as of specific value. The first specimen figured by 
Messrs. Baker and Durand probably belongs to It. platyrhinus , the second and also 
the specimen figured in the first volume of this series cannot be specifically deter- 
mined. 
Sub-generic position of the species. — If all the remains, provisionally referred 
above to JRhinoneros platyrhinus be correctly determined, it would seem probable 
that that species belonged, like the four bicorn species of the European pliocene and 
pleistocene, to a modification of the group, sub-genus, or genus Atelodus, the typical 
members of which are the living African rhinoceroses, and the extinct It. pachygna- 
thus of the Pikermi beds, and to which, in all probability, the Indian pleistocene 
species, It. deccanensis, should be referred. 
If, on the other hand, Ealconer’s reference of a mandible, furnished with two 
pairs of incisors, to this species be correct, it will then belong to the group Gerato - 
rhinus. Very strong reasons have, however, been already advanced against this 
reference. 
Distribution. — As far as I am aware, remains of this species have only been 
found in the typical Siwaliks near the Ganges and Jamna. 
Undetermined Remains. 
Limb-bones. — A large series of limb-bones of rhinoceroses from the Siwaliks 
is contained in the collection of the Indian Museum, but as I have at present 
been unable to refer them to their respective species, it would be useless to notice 
them further on this occasion. It may, however, be observed that even if we 
had not the evidence of the teeth and skulls described above, the existence of at 
least three Siwalik species of rhinoceros could have been predicated from the 
evidence of certain of the limb-bones, such as the astragalus. 
Lower molars . — The extreme difficulty, or even impossibility, of generally 
distinguishing species of fossil rhinoceros from the evidence of detached lower molars 
has already been commented upon. In certain instances, however, there are pecu- 
liarities which serve to distinguish these teeth from the ordinary forms. 
Such an instance is afforded by the lower molar from the Siwaliks of Kushal- 
ghar in the Punjab, represented in figure 3 of plate VI of the preceding volume. 
This tooth is characterised by a distinct wall on the inner side of the e posterior valley.’ 
No such wall is found in the lower molars of any of the species described 
above, and unless this character be an abnormality, it seems probable, as stated in 
the first volume, that this tooth must belong to a fifth species of Siwalik rhinoceros. 
It must, however, be observed that in a mandible of It. javanicus, in my own pos- 
session, the second premolar on the left side only shows a wall in the anterior 
