ELEPHANT AND MASTODON. 59 



sequence, they deviate widely from the uniform succession of three 

 ridges presented by the last deciduous, and the first and second 

 true molars in M. Ohioticus. 



Professor Owen has on two occasions described, in detail, the 

 dentition of M. angustidens, and the result stated in his * Odonto- 

 graphy' is, that he has seen as yet no evidence that the teeth 

 described by Cuvier and by Kaup characterize different species. 

 In his ' British Fossil Mammalia,' he identifies English specimens 

 with some of the typical forms figured by Cuvier, and the number 

 of ridges which he assigns to the different teeth, according to their 

 succession, is 2+3 + 3 to the deciduous molars, 2 to the small 

 premolar, and 3+4 + 5 to the true molars. 1 This formula is liable 

 to the same objections as that put forward by M. de Blainville. In 

 his ' Odontography,' however, published subsequently, Professor 

 Owen describes the teeth of M. angustidens in a different manner, 

 and the number of ridges assigned by him to the successive molars 



in the upper and lower jaws may be expressed thus : 2 T. 3 T" 4 > 



in the deciduous molars, and 4 * 4 "t 5 > in the true molars. 2 This 

 formula, with the exception of the number attributed to the last 

 milk molar of the lower jaw, is precisely the same as that assigned 

 by Dr. Kaup, to his M. longirostris, Professor Owen having 

 referred, in almost every instance, on this occasion, to Kaup's 

 figures, which he quotes as the types of his descriptions. But he 

 still alludes to Cuvier's Dax specimen of M. angustidens, as 

 identical with Kaup's species, although it is represented in the 

 original figure, and described by Cuvier, as three ridged ; and he 

 states in the ' British Fossil Mammalia,' that, the rich series of 

 analogical facts in the dentition of M. giganteus {M. Ohioticus), 

 would "now appear to complete the demonstration of the specific 

 identity of the Mastodon longirostris, and Mastodon angustidens" 

 (p. 290). 



From these details it will be seen how various and opposed the 

 opinions of the best authorities are, up to the present time, regard- 

 ing Mastodon angustidens. In consequence of its rarer occur- 



' « British Fo>.s Mammalia,' p. 286. 2 'Odontography/ p. 619— 23. 



