DENTITION". 227 



Milk molars. True molars. 



4, 8, 12,. 12, 16, 20—? 



4, 8, 12, 12, 16, 20—? 



The last true molars, above and below, commonly present 

 from twenty- two to twenty-four ridges in the Indian Elephant 

 and Mammoth. It remains to be seen, whether, taking into 

 account the greater thickness of these ridges in E. Columbi, 

 they ever exceeded twenty in that species. 



The species clearly belonged to the group Euelephas, and 

 in so far as the dental characters go, its nearest affinity was 

 with the existing Indian Elephant, occupying a position in 

 the series between it and E. antiquus. It differs from the 

 latter by the absence of the constant mesial and sub-angular 

 expansion of the discs of wear, common to it in a minor, and 

 to the African Elephant in a major, degree. The difference 

 from the Indian Elephant is less considerable, consisting 

 chiefly in the enamel-plates being less strongly crimped, and 

 in the discs of wear being more open. Judging from the tri- 

 turating characters of the molars, so far as the analogy of the 

 living species will help us, the food of E. Columbi was pro- 

 bably like that of the Indian species, consisting of branches, 

 twigs, and leaves of certain trees, with reedy grasses and 

 other similar vegetable matters. To my apprehension, they 

 do not indicate succulent matters (i.e. in the botanical sense 

 of the word) to have been the staple food of the species, as 

 conjectured by Messrs. Owen and Blake, nor anything less 

 ligneous than the aliment of the Indian Elephant. The 

 grounds of this opinion will appear fully in the sequel, in dis- 

 cussing the general bearings of the question with reference 

 to the food of other fossil Elephants. 



Of the cranium and other bones of the skeleton, nothing 

 is at present known, although it is probable that abundant 

 remains exist in the North American and Mexican collec- 

 tions. Silliman's 'Journal,' for 1838, contains an account 

 of some elephant bones, discovered in Jackson County, Ohio. 1 

 Among these was a lower jaw, of which a rude sketch is given, 

 along with that of E. primigenius. The rami are represented 

 as converging to a pointed chin and a very contracted sym- 

 physial gutter, totally different from the broad rounded chin 

 and wide gutter which are constant in E. primigenius. In 

 both respects, the figure agrees more with the mandibular 

 form presented by E. Indicus and E. antiquus. The bowed 

 Mexican molar, above described, would suggest that the man- 

 dible of E. Columbi was of a similar form. But the fio-ure 



*a 



1 Silliman's American Journ. 1838, vol. xxxiv. p. 347, et scq. 'On Mather's 

 Eeport on the Geological Survey of Ohio.' 



Q 2 



