44—10 INDIAN TERTIARY AND POST-TERTIARY VERTEBRATA. 
II. sivalensis by the more abrupt angle at the inferior border of the anterior 
extremity, and by the relatively shorter symphysis ; the latter character being shown 
in the following table of measurements ; vis . : — 
Length of symphysis 
Interval between canines 
Depth at pm. 1 
Longer diameter of canine 
)> )) )) 1 - 1 
o 
>» »> 
J? ff ^ 
Ind. Mue. 
F. 147. 
1-2 
0- 9 
1- 33 
H. namadicus i H. sivalensis. 
Brit. Mus. 
A 
> 
t — 
1. 
2. 
v 
3. 
4-1 
6-2 
5-85 
7-1 
7-2 
9-3 
9-9 
80 
4-3 
4-65 
5*2 
4-6 
1-67 
1-86 
2-14 
2 4 
1-23 
1-26 
1-3 
1 35 
0-97 
0-9 
0-92 
1-0 
1-24 
1 43 
1-5 
1-3 
The complete horizontal ramus of this species is not exhibited by any of the 
British Museum specimens, but the highly curved outer surface of the portion 
remaining indicates that the ramus was relatively shorter than in II sivalensis, and 
probably not dissimilar to that of the next species. The short symphysis 
distinguishes the present jaws still more markedly from II. iravaticiis.. The incisors 
exhibit none of the peculiarities of those of II. Idpponcnsis. The distinction of the 
present specimens from the mandible of the succeeding species (AT. palcvindicus') will 
be indicated in the sequel. 
The foregoing comjiarisons sufficiently indicate the specific distinctness of 
II. namadicus from all other known hexaprotodont forms. 
Cranium. — In the “ F.A.S.” (pi. LVII., fig. 1, LVIII., fig. 4) two crania of 
Narbada hippopotami, wanting the premaxillie, are referred to II. palceindicus ; and a 
third specimen in Calcutta^ was also assigned by Falconer to the same species. 
There is apparently, however, not the slightest reason for assigning any of these 
specimens to H. palceindicus rather than to H. namadicus \ and it is quite probable 
that some, or all of them may belong to the latter. It will be better to allude to 
the distinctive characters of these crania under the head of II. palceindicus. 
Distribution. — Remains which can be certainly referred to the present species 
have been obtained only from the Narbadas ; but the old alluvium of the Jainna, 
and the pleistocene of the Pemganga and other rivers, have yielded remains of 
hippopotami, which may probably be referred either to one or other, or to both of 
the Narbada species. 
Species 4 : Hippopotamus pal^indicus, Falc. and Caut. 
Syn. Tetraprotodon palceindicus, F. and C. 
Ilistori /. — With the exception of the mandibles noted above as belonging to 
H. namadicus, the Avhole of the remains of hipjoopotami from the Narbadas figured 
in the “F.A.S.” are referred to the present species; of which no description was 
1 The British Museum specimens of -which the measurements are given are those figured in the “ F.A.S. pi. LVIII. : 
I, fig. 2 (No. 36,840) : 2, fig. 3 (No. 36,838) : 3, fig. 2 (No. 36,839). 
2 Vide “Pal. Mem.,’’ vol. I., p. 147. 
