189—8 
SIWALIK AND NARBADA PROBOSCIDIA. 
now considered merely as varieties of D. giganteum) the longitudinal bridge is inucli 
more developed than in tlie otlier specimens. In a large collection of the molars of 
D. giganteum from Eppelsheim, in the Indian Museum, I also find that there is a 
very great variety in the relative development of this bridge. It seems therefore 
that, as far as regards this longitudinal bridge, no valid grounds for specific distinc- 
tion can be adduced. 
There now remains, therefore, merely the question of the difference of size, and 
this is so slight that it may well be due to sexual difference only : I have, there- 
fore, no hesitation in referring all the three specimens in question to D. penta- 
potamice. 
Comparison with D. indicum and D. giganteum . — It now remains to compare 
these lower jaws with those of the other two well-established sj)ecies of Dmotherium, 
namely, the Indian D. indicum and the Euro]3ean D. giganteum. The remains of 
the first of these species were originally obtained from Perim Island, and consisted 
of a broken molar and a portion of the mandible, which are described in the 
“ Palseontological Memoirs.^ Specimens of the teeth of this second Indian species, 
which was slightly larger than D. giganteum, are described in the sequel of the 
present fasciculus, where the characters which distinguish them from the correspond- 
ing teeth of D. pentapotamice will be found pointed at. Here it will be only neces- 
sary to compare together the dimensions of the three ja'vrs of the last named 
species with the corresponding dimensions of the jaws of D. indicum and D. gigan- 
teum ; the dimensions of the two latter species are nearly all taken from the table 
given by Dr. Ealconer in 
his above- quoted 
notice.' 
^ The three 
jaws of 
D. penta^ 
potayyiicB 
are Respectively 
indicated by 
the 
same 
letters as were used in the table 
given on page 187 of this 
memoir. 
D. pentapotamice. 
rt J\ ^ 
D. indicum. 
H. giganteum. 
Length of last premolar 
1-8 
21 
2-9 
3-3 
Width of 
ditto 
1-74 
2-05 
2-6 
2-7 
Length of first true molar’ 
2-34 
2-4 
40 
3-6 
Width of 
ditto 
1-8 
21 
2-8 
30 
Length of second true molar 
2-4 
2-9 
39 
33 
Widfli of 
ditto 
215 
2-15 
3-5 
2-9 
liength of third true molar 
2-9 
3-18 
... 
3-8 
Width of 
ditto 
2-25 
2 15 
3’5 
Depth of jaw at second premolar 
9-2 
6-9 
Ditto 
at first true molar 
5-2 
... ... 
8-7 
6-2 
Ditto 
at second true molar 
5-4 
6-6 
Ditto 
at third true molar 
58 
6-4 
Width of jaw at second premolar 
30 
5-1 
4-0 
Ditto 
at first true molar 
3-4 
6-4 
5-0 
Ditto 
at second true molar 
3'4 
5o 
Ditto 
at third true molar 
4-1 
fil 
* Vol. I, pp. 39fi, 404- 
" Ihid., p. 407. 
