ELEPHANT AND MASTODON. 



61 



lower jaw, which exhibited no vestige of a tusk, and which 

 were usually considered to belong to M. Oldoticus. Mr. W. 

 Cooper, in consequence, immediately questioned the accuracy 

 of Godman's inference, and insisted that the inferior tusks 

 indicated merely differences dependent on age and probably 

 sex; that they were possessed by the young animals, but 

 were shed during the increase of age, the period of their fall 

 varying with the individual.^ Mr. Titian Peale suggested 

 that these inferior tusks might be a distinctive mark of yoiing 

 males.^ Dr. Harlan adopted the same view,^ and referred 

 to the corneous appendages in several genera of the Rumi- 

 nantia as analagous distinctive characters between males and 

 females. JSTotwithstanding the force of these objections. Dr. 

 Isaac Hays, in 1831, not merely maintained the correctness 

 of Dr. Godman's opinion regarding the distinctness of Tetra- 

 caulodon, but attempted to distinguish two additional species 

 of this nominal genus under the titles of T. Gollinsii and T. 

 Godmcmi, besides two new North American species of Masto- 

 don.* The memoir in which these opinions were advanced 

 is illustrated by an excellent and copious series of figures, 

 exhibiting the dentition of M. Oliioticus, from a very early to 

 the adult stage ; and although Dr. Hays has entirely failed 

 in sustaining the genus Tetracaulodon, or the species which 

 he proposed, his memoir has served as an important con- 

 tribution to palaeontology, by showing that the number of 

 molars developed during life, in M. Oliioticus, sviccessively . 

 from behmd, amounts to six. These he has traced from the 

 first to the last with great care, in the lower jaw, and estab- 

 lished the position and characters of each by the comparison 

 of a large number of specimens. 



Whilst this discussion was taking place in America, the 

 discovery was made of a similar structure in a European 

 Sj^eeies of Mastodon, by Dr. Kaup. This distinguished palae- 

 ontologist first proved the existence of two deflected and 

 recurved tusks of large size, in the lower jaw of his colossal 

 genus DinotJoerium, the teeth of which had been referred by 

 Cuvier to a gigantic kind of Tapir. Soon afterwards, at 

 Eppelsheim, in the same arenaceous deposit which had 

 yielded the Dinotherian remains, he discovered an adult 

 lower jaw of a species of Mastodon, which presented a re- 

 markable semi-cylindrical and beak-shaped elongation of the 



' "W. Cooper. ' Lyceum of Nat. His- 

 tory of New York; April 1830 ; 'Silli- 

 man's Joiirn.' voL xix. p. 159 ; and 

 Featlierstonhaugli's ' Monthly American 

 Joiirn. of Geol.' vol. i. p. 158. 



2 Titian E. Peale, quoted in Dr. 



Hay's Memoir, Amer. Phil. Trans. New 

 Ser. Tol. iv. p. 318. 



' Harlan, ' Med. and Phys. Research,' 

 p. 25i! 



* Hays, loc. cit. pp. 317-337. 



