22 
INDIAN TERTIARY AND POST-TERTIARY VERTEBRATA. 
m. 2 .^ In the Indian tooth, however, the anterior accessory column seems to have 
been relatively larger ; and extended across the median antero-posterior fissure, 
instead of being confined to its inner side. There apjDears a certain amount of 
variation in the degree of development of the accessory tubercles in European 
specimens of of M. angustidens^ ; a specimen figured by Kaup^ being apparently 
very close to the Indian tooth. 
The molar represented in plate IV., fig. 1, is a still more worn specimen of the 
same tooth : it is slightly wider than the last ; but as similar variations obtain among 
European specimens this difference cannot be considered as of more than individual 
value. In this much-Avorn tooth, not only have the dentine surfaces of the separate 
columns united, but those of the first and second ridges have likewise coalesced ; the 
extremely worn dentine surfaces assuming a regular elliptical shape. Traces of the 
outer column of the last ridge still persist.^ Precisely similar conditions of wear 
obtain in European teeth of 31. angustidens.^ 
If the two teeth described aboAm be compared Avith the corresiAonding tooth of 
the Siwalik 31. falconeid,^ they Avill be found to differ by their greatly inferior size. 
They also differ by their smaller hind talon, and the greater deAmlopmeiit of the 
anterior accessory column (a), and the consequently less regular trefoils formed by 
the dentine surfaces of the inner columns. The difference in size is indeed so ffreat 
that the teeth under consideration correspond in this respect with m. 1 rather than 
m. 2 of 31. falconeri. An almost uiiAVorn molar of that species is represented in vol. I., 
pi. XXXIII., fig. 3, Avhere it is regarded as m7I : from its regularly oblong form 
this tooth is, hoAvever, more jDrobably ni. ] , of the right side. It exhibits equally 
well the differences from the teeth under consideration, pointed out in comparing 
them with m. 2 of the same species. The large fore-and-aft talons are Avell displayed. 
From the second true molar of 31. iiandionis^ the present specimens are likewise 
distinguished by their greatly inferior size. The crown of the latter (although the 
different degree of wear of the specimens is not Amry fuAmufable for comparison) is 
of a more comj)lex structure, owing to the greater number of accessory columns, 
and the fine plications into Avhich the enamel is thrown. The form of the Avorn 
dentine surfaces is not very unlike in the tAvo ; although those of the present species have 
a greater tendency to a trefoil shape : the tooth of 31. pandionis is further distinguished 
by the presence of a large amount of cement. The Biigti teeth agree more nearly in size 
with nu 1 of 31. pandionis of which an unworn specimen is represented in plate V., 
fig. 5 : exhibiting Avell the highly complex crown, Avith its tall columns. This tooth 
1 Specimens of these teeth in nearly the same condition of wear are figured hy Herr Vacek {op. cif., pi. V., figs. 3, 4) : 
they are viewed from the outer side. 
2 Compare Meyer, op. cit., pi. I., fig. 5 : pi. III., fig. 7. .3 “Beitrage,” pt. 3, pi. III. 
4 As this tooth might he mistaken for mTi of Dinotherium, it may he well to point out that it is distinguished from that 
tooth in I), indicum (vol. I., pi. XXXI., fig. 2), hy the circumstances that in the latter the dentine surfaces of the ridges 
assume an irregular shape when most worn ; the reverse obtaining in the present teeth. The molar of Binoiheriwn is also 
distinguished hy its much thicker enamel. 
6 Compare Vacek, op. cit., pi. V., fig. 4. 6 Supra, vol. 1., pi. XXXII., fig. 1. 7 dl/id, pi. XXXVa. 
