90 
liecoriU of the Geological Siirveg of India. 
[voL. XI, 
to a very large animal. Tlie tooth is brachydont, and the enamel is less rugose 
than in any of the Sivatherioids, and I therefore refer it to the Giraffes. The 
tooth posteriorly has a simple oval-shaped pit on its summit equal to about one- 
thii'd the whole length; anteriorly it has a simple trenchant edge; it is therefore 
different in form from the corresponding tooth of either the Giraffes or Sivathe¬ 
rioids, and probably indicates a now genus, though I can at present say nothing 
more definite in regard to it. 
We have now to turn our attention to the genus Hydaspitlierium, of the upper 
molars of which Mr. Theobald has sent a considerable number of specimens from 
the Punjab. In a forthcoming memoir on the cranium of H. megacepJialnm now in 
the press, ^ I have shortly noticed the upper teeth of that species, as well as a single 
detached specimen of an upper molar, and I have also pointed out the characters 
which distinguished these teeth from the molars of Sivathermm. The new speci¬ 
mens of upper molars have conclusively proved the existence of at least one new 
species, while another species is known upon the evidence of a lower jaw. 
The notices of the specimens of this genus will be somewhat short, ns many of 
them will be figured on a future occasion. 
The first specimen that requires notice is a detached left upper molar which 
is a typical specimen; this tooth is distinguished from that of Swatliervum gigan- 
tewm by its smaller size, by the rugosity of the enamel being less coarse, by the 
absence of foldings in the central enamel island, and by the form of the external 
surface or dorsum. This latter character it will bo necessary to examine rather 
more closely. In the upper molars of Sivatlierium, the dorsum of the hinder barrel 
carries three bold ridges or cost®, of nearly equal size; the dorsum of the fore 
bari’el contains two similarly bold ridges or cost®. In typical specimens of the 
upper molars of Hydaspitheriwm, megaceplialuim, the mesial ridges or cost® are 
very much less prominent; the one on the hind lobe being especially indistinct. 
Among the specimens obtained this year are the two last upper molars of the 
right side, which agree exactly in size with the last-mentioned tooth; in these 
specimens the cost® are still more indistinct on the dorsa of the hinder lobes, 
this surface being indeed almost evenly concave, and exceedingly different from 
the same surface in the molars of Sivrdliemm. Still, the difference in the form 
of these teeth and of the typical molars of H. megaceflialum is so slight that 1 
for the present, at all events, consider it best to refer these molars to that species, 
classing them only as a variety. In the table below I have given the measure¬ 
ments of the single typical tooth which I call variety a, and in the second column 
those of the two aberrant teeth which I call variety I; in the third column I have 
given the dimensions of the two last molars of S. giganteum — 
llydasp. 
var, a. 
var. i 
Sivath. 
lu. 
In. 
In. 
Length of last molar 
1-56 
1-62 
2-00 
Width of „ „ 
1-60 
1-63 
2-38 
Length of penultimate molar . 
• > 4 . 
1-59 
1-68 
Width of „ „ 
• 
1-70 
2-20 
Height of „ ,, 
• »»• 
1'20 
... 
* Palieontologiii Indica, Ser. X, Vol. I, pt. 3. 
