192 FAUNA ANTIQUA SIVALENSIS. 



Tossiles ' (Plate YI. figs. 3-5 and 8-10), between tlie teeth of 

 whicli two extinct quadrupeds those of the Sewalik fossil are 

 intermediate in size. In general form and in the principal 

 distinctive marks they agree closely with the teeth of the 

 typical European species of Anoplotherium, as described by 

 Cuvier ; but they differ from those types in some particulars 

 requiring special notice ; they are closely allied to the teeth 

 of the Chalicotherium of Kaup. 



The three rear molars considerably exceed, in all their 

 dimensions, the corresponding teeth of A. commune ; and 

 the two rear molars also differ from the corresponding teeth 

 of A. commune in the following respect, that their width is 

 greater than their length. This proportional compression 

 lengthwise belongs to the last two pre-molars of the SewaHk 

 fossil, and it holds also with the back molars of the Chalico- 

 therium. The outer surface presents, both vertically and 

 horizontally, the usual double chevron, or W-form of Ano- 

 plotherium, with the three sahent vertical brdges swelling up 

 from the Isase to the crown; but with this difference from 

 Anojylotherium, that the surface of the re-entering angles is 

 more incliued inwards. The latter point is one of agree- 

 ment with Chalicotherium, in which the outer ridge of the 

 crown is so inflected as to be brought into the middle of the 

 plane of the tooth. The interspaces forming these re-enter- 

 ing angles are more unequal than in A. commune, the an- 

 terior one being much the broader. The posterior one in the 

 last molar is placed very obKquely, sloping backwards and 

 inwards. In these respects also the fossil agrees closely with 

 Chalicotherium. The vertical bulges, more especially the 

 rear one of the last molar, are slightly notched near the 

 apex into a lobule of the enamel, but much less so than in 

 Chalicotherium. In consequence of the progress of wear 

 being more advanced in the two other back molars, they 

 show no indications of this notch. 



From the great inflection of the outer surface, the longi- 

 tudinal ridge of the crown is strongly zig-zagged. The apex 

 of the anterior re-entering angle gives off a transverse ridge, 

 which is much inclined downwards, and joins on with the 

 base of the isolated conical cusp (a, a', a") in the anterior 

 and inner comer of the tooth, a cusp characteristic of Ano- 

 plotherium. In the Sewalik species, as in Chalicotherium, 

 this cusp is much larger, more pointed, surrounded by deeper 

 hollows, and more in relief than it is in ^. commune. It is 

 even more developed than in Chalicotherium. The apex of 

 the posterior re-entering angle gives off a like transverse 

 ridge which sweeps round into the posterior side, and forms 

 in the germ a sort of three-sided pyramid, connected by a 



