OF THE SIVALIK HILLS. 49 



a drawing is given in Professor Buckland's work alluded to, little resem- 

 blance is recognizable. The Lancashire fossil has the four incisors, with a 

 lower jaw of proportions apparently quite unique, and with a prominency of 

 arch in the nasal bone equally so. We may however remark the elevated 

 occipital crest, and the fall towards the space between the orbits which 

 exists in the Lancashire fossil, as this appears to be general to the fossil 

 species, relieving the head from that straightness of chafFron which is 

 noted as one of the peculiarities of the African Hippopotamus. 



Having concluded our remarks regarding the Hippopotamus Sivalensis? 

 we now come to another and a smaller species of this genus which appears to 

 have been less numerous, but with the remains of which we are sufficiently 

 provided, although in the possession of only two fragments ; one the imper- 

 fect skull of an old animal with the teeth much worn ; and the other the right 

 side of the lower jaw, shewing an unusual contraction or narrowness in the 

 symphisis ; this latter fragment contains five molars, the rear one perfect, and 

 the last false molar sufficiently marked to establish the age of the animal ; 

 this was past adult, the first and second advanced cylinders of the rear 

 molar being worn, and the third or rear one in the state of germ, but fully 

 out of the alveolus. The form of this tooth differs from the great Hippo- 

 potamus in the absence of the trefoil, the wear of the coronals of each pair 

 of collines taking a crescentic form outwards, not unlike that of ruiliinants, 

 the grinding surface sloping outwards, very similar to the description given 

 by CuviER of the Hippopotamus Minutus. The form of the jaw, however, is 

 peculiar, the marked features consisting of a general slenderness of proportions, 

 and an inequality in the depth, which being contracted at the point of the 

 descending process, gets gradually deeper, and diminishes again still more 

 gradually up to the symphisis : in the great Hippopotamus we have a 

 straight, thick, massive jaw. The foramen for the artery distinctly exhi- 

 bited in the fossil, enters just behind the last tooth on the internal face of 

 the ramus, and shews itself again on the opposite side j ust between and 

 under the fourth and fifth molar, in a markedly large hole from which, to 



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