624 UNGULATES. 



the other ; and on the lower half of the more convex (outer) side 

 of the tusk, faint traces were distinguished of longitudinal grooves, 

 about a line in breadth. In all these characters, the fragment in 

 question agreed with a similar fragment of a tusk, ten inches in 

 length, obtained from the miocene, or older pliocene tertiary deposits 

 at Eppelsheim, in Germany, which specimen Dr. Kaup had ascer- 

 tained to belong to the lower jaw of the same species of Mastodon. 



The division of the transverse eminences of the surface of the 

 molar teeth into large rounded mammillae, often placed sub-alter- 

 nately, is common, with slight modifications, to the European 

 Mastodon angustidens, with allied species in South America, Australia, 

 and Southern Asia. 



228. Transitional Mastodons. — Mr. Clift(l) has described and 

 beautifully illustrated the dentition of one of the Asiatic Mastodons 

 with molar teeth, which differ chiefly from those of the Mast, angus- 

 tidens in their greater relative breadth : he has, therefore, termed the 

 species Mast. latidens.(2) The last lower molar tooth is figured in PI. 38, 

 fig. 1, of the volume cited : it presents a grinding surface nine inches 

 in length, and nearly four inches in breadth ; divided into six trans- 

 verse eminences and a posterior talon ; each eminence is divided into 

 two principal mammillae, and these are again sub-divided into two 

 smaller rounded mammillae, except in the fifth eminence, which 

 consists only of the two principal mammillae, whilst the sixth 

 division or talon, is formed by a single large obtuse eminence. (3) 



In the same plate Mr. Clift figures part of the lower jaw with 

 the last molar tooth of another more remarkable species of Probosci- 

 dian, which he has termed Mastodon elephanto'ides.{4) This tooth 

 (PL 145, fig. 2) is twelve inches in antero-posterior extent, and three 

 inches in breadth : its grinding surface is divided into ten nearly 

 equal low transverse ridges, the summits of which are sub-divided 

 into five or six small and equal obtuse mammillae. The interspaces 

 of the ridges are not filled with cement, as in the true Elephants ; 



(1) Geological Transactions, Second Series, vol. ii, 1829, p. 369. 



(2) This appropriate name was suggested to Mr. Clift by Mr. Broderip, the learned 

 Secretary of the Geological Society. 



(3) PL 145, fig. 1. This and other characteristic remains of the M. latidens were dis- 

 covered in newer tertiary deposits on the banks of the Irawadi, in Ava. 



(4) This name was likewise suggested by Mr. Broderip, the species was found in Ava. 



