220 FAUNA ANTIQUA SIVALENSIS. 



with Macrauchenia Patagonica, according to the lower jaw so 

 determined by Owen,' and with Rhinoceros ; but both of 

 these genera are without the posterior ' talon ' to the lower 

 back molars, found in the Sewalik form. Chalicotheriuin 

 differs also from Rhinoceros in the equal height of the an- 

 terior and posterior lobes. 



The inferior molars decrease very uniformly in size from 

 the last true molar to the penultimate or first (theoretically 

 the second) premolar, which has a simple cuneiform crown re- 

 sembling in size and shape the lower canine. It is implanted 

 by a double confluent fang. The second premolar (theore- 

 tically the third) exhibits a reduced condition of the double 

 crescent of the back molars, the internal point of junction 

 being bifid and elevated as in them. The last premolar 

 (p.m. 3) is double-barrelled and differs in no respect from the 

 true molars except in the absence of the posterior talon. A 

 question may be raised, whether the first premolar is not re- 

 presented b)^ the tooth above described as an inferior canine. 

 But its advanced position in the jaw, close to the incisive 

 border and the thick procumbent simple fang by which it is 

 implanted, appear to be conclusive against a view of this 

 kind. 



In consequence of the close resemblance between the upper 

 molars of the Sewalik and Ej)pelsheim species of Chalicothe- 

 rium, it might be expected that the lower molars would also 

 agree. Kaup describes and figures two teeth which he refers 

 to the lower jaw of Chalicotherium. I have compared casts 

 of these with the lower molar of Chalicotherium Sivalense, 

 and the generic accordance was found to be complete. The 

 one (Kaup, loc. cit., tab. vii. fig. 5) is a worn last molar of 

 the left side, broken behind (regarded by Kaup as penulti- 

 mate). In correspondence with the upper molar, the crown 

 is proportionally broader and less elevated than in the 

 Sewalik species ; the anterior edge of the front lobe is not 

 so much inclined, but the point in which it terminates shelves 

 backwards towards the base of the middle internal lobe, as 

 in the Indian fossil ; the internal point at the confluence of 

 the two crescents is also considerably elevated, and the 

 outer termination of a posterior talon is discernible ; the 

 other tooth is an antepenultimate true molar of the right 

 side. Excepting the greater width and lower elevation of 

 the crown it agrees closely with the corresponding tooth of 

 Chalicotherium Sivalense in form and proportional size. It 

 would appear that this accordance runs throughout the 



' Odontography, p. 602, pi. 136, fig. 7. The specimen is in the British Museum; 



'Palseont. CoU.' No. 19,950. 



