ELEPHANT AND MASTODON. 49 



tooth figured in the section measures 5^ inches in length. M. 

 latidens, of the known forms of Mastodon, is that which is most 

 nearlv allied to E. Cliftii, and through that species to the true 

 Elephants. One or more intermediate links perhaps still re- 

 main to be discovered. It closely resembles the European M. 

 Arvernensis (M. longirostris of Kaup) in the form of the molars. 

 The correspondence is so great, in the last milk molar, and in the 

 antepenultimate and penultimate true molars, that they have been 

 regarded as identical species. 



Fig. 10 a represents a section of the last molar of the upper 

 jaw of an Indian fossil species named Mastodon Sivalensis in this 

 work. The ridges in this species are more complex in their com- 

 position than in M. latidens. The crown is traversed by a longi- 

 tudinal furrow which bisects them, each division being composed of 

 a pair of contiguous or connate conical mammilla?, placed more or 

 less alternately. The hollows are in consequence interrupted. 

 This tooth, like its equivalent in M. latidens, consists of five prin- 

 cipal ridges, with a subordinate ridge in front, and a ' talon' ridge 

 behind. Eight divisions of the ivory may be counted in the figure, 

 the smaller segments arising from the direction in which the sec- 

 tion has been made through the alternate mammillae. The ridges 

 are approximated, and the layer of enamel bears a large proportion 

 to the conical lobe of ivory which it invests. The cement is en- 

 tirely wanting, except in the bottom of the clefts. This tooth mea- 

 sures about seven inches in length. 



Fig. 10 b shows a section of a fragment comprising the greater 

 part of the last lower molar of the same species. There is a 

 similar alternate arrangement of the mammillae, and the tooth 

 differs from the corresponding upper molar, only in being compli- 

 cated with an additional ridge. 



The teeth of this species bear an exceedingly close resemblance 

 to certain of the European fossil grinders, which have been de- 

 scribed under the indefinite name of M. angustidens. The three 

 species, M. latidens, M. Arvernensis, and M. Sivalensis, with 

 perhaps a fourth, of doubtful determination, constitute a particular 

 section of Mastodon, characterized by the same numerical division 



E 



