48 



NOTE ON THE FOSSIL HIPPOPOTAMUS 



it with the fossil described by Cuvier as belonging to the cabinet of the 

 Grand Duke of Tuscany and figured in the first volume of the Ossemens 

 Fossiles. The distinctive differences will be perhaps best observed by a 

 reference to the table of measurements : we see however that our fossil in 

 the gradual slope of the malar process towards the cheek corresponds ; but 

 differs completely in the hollow formed at tliis point between the jugal bone 

 and canine alveolus which in our fossil is more abrupt and marked. The 

 length of the parietal region of the European fossil is even less than 

 that of the existing animal, and their proportions relatively with the bones 

 of the face less. In the Sivalik fossil, the advanced position of the orbit 

 completely modifies the whole form, and, by equalizing the proportions of 

 the anterior and posterior divisions, gives a new style of appearance to the 

 cranium. In the fall of the occipital crest towards the region between the 

 orbits, and a consequent increased height of occipital surface, the Sivalik 

 and Florence fossils also agree. In the proportion of the frontal surface to 

 the area of the rest of the skull the resemblance also holds good ; but we 

 have the same difference in the relative position of the canines to the 

 molars ; the Florence and African species corresponding in this respect. 

 The grand distinction of the incisives and canines, both in form and num- 

 ber, is peculiar to the Hippopotamus Sivalensis. In the lower jaw the space 

 between the two branches, and the angle which is internally formed by them 

 does not resemble that of the Florence fossil ; but, as we before remarked, 

 is more assimilated to that of the existing animal in being round at the angle, 

 and the whole interval space being more open : the descending process of 

 the ramus differs, as explained before; and the form of the anterior angle of 

 the jaw below the canines is somewhat similar and not so gradually round- 

 ed off as in the living animal. The difference in size and number of the 

 incisors leads to a difference which, as before noted in the comparison with 

 the living animal, needs not be made the subject of further remark here. 



With the Hippopotamus Sivalensis and that figured in the ReliquicB 

 DiluviancF, described as found in a peat bog in Lancashire, and of which 



