ELEPHANT AND MASTODON. 49 



dental formulse in the molars as points of generic distinction 

 between elephant and mastodon, attributing eight molars in 

 each side to the former, and only six to the latter. 



Cuvier, except in what regards his hypothetical explanation 

 of the formation of the dental tissues, has described with 

 admirable clearness and in great detail the structure and 

 mode of growth of the teeth in the elephant. But he had 

 assuredly arrived at no accurate idea of the true division of 

 the molar series into milk and permanent grinders. He 

 makes no attempt to show where the deciduous series termi- 

 nates and the true molars begin, although so particular upon 

 this point in his descriptions of the dental system in the 

 ordinary Pachydermata and Ruminantia. In fact, the term 

 ' dent de lait ' is but rarely aj)plied in his elephant descrip- 

 tions ; and in these instances it has evidently reference more 

 to the immature age of the animal than in the ordinary sense 

 to a deciduous tooth which is expelled by a vertical successor. 

 Having adopted the excessive numerical formula of Corse, 

 this great anatomist was led to believe that the successional 

 premolars, instead of being suppressed, are developed behind 

 the milk teeth. The language in which this remarkable 

 opinion is expressed is clear and explicit : — ' L'on pourroit 

 dire que les dents de remplacement de I'elephant viennent 

 derriere ses dents de lait, au lieu de venir dessus ou dessous, 

 conime dans les autres animaux.' ^ 



The discovery of the entire set of molars in Mastodon 

 Ohioticus, by Dr. Hays,^ in 1834, and in M. longirostris, by Dr. 

 Kaup,3 in 1835, had clearly established that the antero- 

 posterior series in these species does not exceed six, and 

 paved the way for an accurate knowledge of the dentition of 

 the elephant, when M. de Blainville published, in 1844, the 

 osteographical memoir upon this genus contained in his great 

 work. This distinguished anatomist, in his remarks upon 

 the dentition of the Dugongs, first states that the elephants 

 (in which he includes the mastodons) have neither milk teeth 

 nor vertical successional teeth.* His words are — ' Amsi l'on 

 pent dire que chez les dugongs et chez les autres lamantins, 

 ainsi que chez les elephants, il n'y a ni dents de lait ni dents 

 de remplacement, comme chez la plupart des autres mammi- 

 fergs ; ceUes-ci poussant, pour ainsi dire, celles-la de bas en 

 haut, et formant ainsi deux rangees superposees ; mais que 

 toutes les dents que doit avoir I'animal dans le cours de sa vie 

 entiere forment une seule ligne, un seul rang, une sorte de 



' Cuvier, Oss. Fossil, torn. i. p. 39, 

 4to. edit. 1821. 



^ Hays, Amer, Phil. Trans, vol. iv. 

 p. 320, 1834. 



VOL. U ' E 



^ Kaup, Oss. Fossil, pt. iv. pp. 65-89, 

 1835. 



^ De Blainville, Osteograpliie, ' Maua- 

 tus,' p. 75. 



