50 



NOTE ON THE FOSSIL HIPPOPOTAMUS 



the space between the tusk and the most advanced molar, there is a deep 

 channel or indentation running upwards in a curved line parallel to the 

 lower face of the jaw. The anterior and posterior portions of this beautiful 

 fragment are unfortunately wanting, but a small part of the symphisis, at 

 which point the fossil terminates, is distinctly marked, as well as the trans- 

 verse section of the canine or tusk which as in the large animal is pear- 

 shaped. A considerable portion of the anterior extremity is wanting, and 

 with the tusk the fracture shews only one alveolus or hollow for an incisive 

 tooth : the existence of two, however, can hardly be doubted, but the 

 narrowness of the front may make a greater number than four between the 

 two canines problematical. The ramus of this specimen is strongly marked 

 on its anterior part by an elevated ridge pointing angularly forwards, and 

 pushing forward a nearly flat surface to the centre of the rear tooth ; the 

 descending process is unfortunately too much broken to allow of our speak- 

 ing decidedly, but the angle of departure from the straight line of the 

 jaw is abrupt. The other remains of this smaller species to which we have 

 alluded, consist of a skull, the front and rear of which is broken off, and one 

 line of molars with the palate only perfect. The superimposed cranium 

 would appear to be contorted by pressure, as is by no means uncommon, 

 but this circumstance would lead us to refrain from an attempt at cha- 

 racterizing its peculiarities. The molars consist of the three rear 

 permanent ones, and the last false molar, this latter one exhibiting 

 the crescentic form of wear on its coronal surface described as peculiar 

 to the first fragment. The other molars are much worn, and therefore with 

 the exception of the encircling ridge of enamel, we have but those flexures 

 which would have brought us to a correct conclusion. These molars are 

 remarkably broad in proportion to their antero-posterior dimensions, and 

 have an oblique grinding surface as before described in the other fragment. 

 We may remark, that should these two remains belong to a small Hippopo- 

 tamus of the same species, the great diflerence in the breadth of the grinding 

 surface in the upper and lower jaws, as marked as is in the Rhinoceros, 



