1843.] 237 



inwards. The latter point is one of agreement 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-entering angles are more unequal than in A. commune, the 

 anterior one being much the broader. The posterior one in the last 

 molar is placed very obliquely, 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 pro- 

 gress of wear being more advanced in the two other back molars, 

 they show no indications of this notch. 



From the great inflexion of the outer surface, the longitudinal 

 ridge of the crown is strongly zigzaged. The apex of the anterior 

 re-entering angle gives oflF 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 corner of the tooth, a cusp cha- 

 racteristic of Anoplotheriura. In the Sewalik species, as in Chali- 

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

 deeper hollows, and more in relief than it is in A. 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 low ridge with the cusp. The 

 anterior border of the crown is formed of a similar low ridge, sweep- 

 ing round to the inner side of the cusp, upon which it terminates 

 near the middle of the cusp. This ridge is less developed than in 

 A. commune. 



The penultimate and antepenultimate are so like the last molar, 

 that the authors deem it sufiicient to refer to the figures. The pe- 

 nultimate is the largest of the three, and the antepenultimate consi- 

 derably the smallest. There is in all the three molars a strong 

 development of the cusp ; though, from the diff'erent stages of wearing, 

 it shows diff^erently in the several teeth. In the back tooth it is 

 intact and has a sharp edge ; in the penultimate the point is just 

 worn off into a slight oblique facet ; in the antepenultimate it is 

 ground low down into a circular depressed disc, surrounded by a ring 

 of enamel. 



The other teeth in the specimen (PI. II. fig, 1.) are the last three 

 false molars. What was the entire number of this series, whether 

 it extended to four, as in A. commune, or was limited to three, the 

 specimen afi'ords no certain indication. If there was a fourth tooth 

 (which is most probable), it must have been in a rudimentary or 

 reduced state, as in the rhinoceros, and must have been disconnected 

 from the rest of the series by being placed somewhat forwards in a 

 diasteme ; for no indication is obtained, from the appearance of the 

 anterior tooth, or from remains of any alveolus, that there was an- 

 other tooth close in front of the sixth. These three premolars, taken 

 in succession from rear to front, diminish rapidly in size ; and in the 

 aggregate are much shorter than the same three teething, commune, 



t2 



