343—166 INDIAN TERTIARY AND POST-TERTIARY VERTEBRATA. 
characters among existing Felidce } In both sexes M. palceindicus must be regarded as 
a more powerful and larger animal than M. sivalensis. 
Compared with European and American species the mandible of the male of 
the present species is distinguished from all, with the exception of M. meganthereon , 
by the earlier commencement of the descending symphysial expansion : even in that 
species, however, this expansion has by no means the same vertical extent ; while the 
ridge at the anterior border of the lateral surface is less strongly marked, and more 
removed from the vertical ; and the diastema is relatively longer. The mandible of 
the skull of M. neogceus figured by De Blainville, which from its large upper canines 
is certainty that of a male, is distinguished by its longer diastema, smaller symphysial 
expansion, and generally more slender form ; as well as by the small pm. S. The 
lower -jaw of M. necator is like that of M. sivalensis. The mandible of the female of 
M. palceindicus is more like that of M. cultridens , 2 but probably had a shorter diastema, 
and a smaller pm. 3. M. palmidens is readily distinguished by its inferior size and the 
complex character of pm.. 4. 
In respect of the size of pm. 3, the present species seems to indicate a form 
intermediate between the machserodonts of the Old and New Worlds. 
Cranium . — In plate N., figs. 1, la, lb, lc, of the “ F.A.S.” there are given four 
views (~) of the occipital portion of a carnivorous skull from the Siwaliks, in the 
British Museum (No. 39,728) ; referred in the description of the plate 3 to M. 
sivalensis ; but subsequent ly by Mr. Bose 4 to his M. palceindicus. The specimen is 
broken off anteriorly in front of the post-orbital process of the frontal by a fracture 
extending obliquely backwards to the zygomatic process of the squamosal; the 
portion still remaining is fairly perfect, and as it comprehends the same part as the 
fragmentary skull of M. sivalensis represented in woodcut fig. 20, it is easy to 
compare the two. In the first place, the present skull considerably exceeds in size 
that of M. sivalensis ; the diameter across the occipital condyles being respectively 
2-53 and 2 - 0 inches. The present specimen has a much produced zygomatic process, 
well preserved on the right side, 5 bearing a long post-glenoid process ; the mastoid 
process, although broken interiorly, is also similarly produced, and below the auditory 
meatus is in contact with the zygomatic process. This proves not only that the specimen 
belongs to Macliaerodus , but also to a form allied to M. sivalensis and the American 
species. Irrespective of its superior size, this skull differs from that of M. sivalensis, 
firstly, by the proper occipital surface forming an inverted V, in place of having 
rounded lateral borders ; secondly, by the lateral borders of the occipital crest, when 
viewed from the side, forming a nearly straight line, in place of bending backwards 
above the condyles ; thirdly, by the posterior border of the mastoid process being 
set more obliquely to the plane of the occiput ; and, fourthly, by the lesser develop- 
1 E. g., F. leo. 
2 The specimen figured by Wagner {op. cit.) : as all the specimens known (and these are numerous) are similar, it is to 
he presumed that there was no marked difference in the form of the mandible of the two sexes. 
3 “ Pal. Mem vol I., p. 550. 4 Op. cit., p. 126. 5 “ F.A.S.,” pi. N., fig. lc. 
