PAiiT l.j Lydchker: Notnes of Siwalik Mammals. 91 
The two conjoined teeth shew a faint cingulum at the base of the inner 
columns, which is not observable in the isolated tooth or in the teeth of the cranium 
of H. megacephaluni. We have now to consider several other specimens of 
upper teeth, which have eonsidei'ablc resemblance to the two last specimens, but 
which arc of larger size, and which still further diverge from the Simtheriwn type, 
and which must, I think, undoubtedly bo referred to a second species of the genus 
Ilydaspitherimn, for which I propose the name of H. grande. The specimen 
which I will h*re select for notice is a penultimate upper molar of the loft side 
from the Punjab. This tooth agrees with the teeth of the last specimen in its 
general form, the dorsum of the posterior barrel overlapping that of the anterior 
column (owing to the oblique position in which they arc placed), and the enamel 
being rugose, though less so than in Swathenwni, and there being no crenulation of 
the enamel in the central pits. 
The chief differences of this tooth from those of variety I of the last species, 
irrespective of size, are, that the crown is relatively much higher; that the anterior 
costa of the dorsum of the hinder lobe is more prominent and curves more forwards, 
and that there is no median costa on this surface, which is more concave than in 
the last specimen ; the median costa on the dorsum of the fore lobe is also 
much less developed; there is no trace of any cingulum on the internal surface of 
this tooth, nor of any tubercle in the median valley; the summits of the lobes have 
hardly been touched by wear. The dimensions of this specimen arc compared 
below with the above described penultimate upper molar of variety h of 
II. megacephalum — 
H grande. 
E. mega. 
Length of crown 
In. 
In. 
1-80 
1-59 
Width of „ 
1-80 
1-70 
Height of „ 
1-60 
1-20 
This tooth, therefore, is squarer than that of II. megacepliahi-m, and, differing 
by only OT inch in width, differs by 0'4 in the height of the crown. These differ¬ 
ences, I think, amply justify specific distinction ; these teeth from the absence or 
slight development of the median dorsal costaa present no resemblance to those 
of either Sivatliermm or Braniatherium. They arc nearest, of course, to the variety 
h of Hydasgntliermm mogaceplMhmi, the latter forming a connection between the pre¬ 
sent specimen and var. a of H. megacepltalum, and those again with SivatJierium,. 
As I have before hinted, it is not impossible that the teeth of variety I of H. 
megacephalum may really belong to a distinct species, though I do not think wo 
are justified in making any distinction on the evidence of these teeth alone, as 
they are so close to those of variety a. 
In addition to the above specimens, Mr. Theobald has obtained three detached 
upper molars of the same species from the village of Asnot, as well as the two 
last upper milk-molars of the right side, and two detached specimens of penultimate 
upper milk-molars of the same side, which from their size and foiun I have little 
doubt must bo referred to II. gra/nde. The ultimate milk-molar repeats the 
characters on a smaller scale of the larger permanent teeth; the penultimate milk- 
molar has the first barrel produced into a. point anteriorly-, which proves that the 
