62 



FAUNA ANTIQUA SIVALENSIS. 



s}Tnpliysis, forming the sheaths of two inferior tusks, while 

 the molar teeth exhibited the characters attributed by Cuvier 

 to a portion of the specimens included by him under the 

 names of M. angustidens. Kaup, after recognising' the struc- 

 ture, at first adopted Godman's genus for the reception of 

 his species, which he named T. longirostris;^ but, subse- 

 quently, in his great work upon the Eppelsheim fossils,^ he 

 admitted the force of the objections raised by the American 

 naturahsts against the generic importance of the inferior 

 tusks in Tetracaulodon, and referred the Eppelsheim fossil to 

 the genus Mastodon, retaining the same specific name. He 

 extended the observations made by von Meyer on M. Arver- 

 nensis, which he considered to be the yomig of M. longirostris. 

 He traced the dental succession from the earliest to the adult 

 stage confirming the observations made by Hays on M. 

 OMoticus, by showing that six molars are developed in the 

 Eui'opean species during life, in antero-posterior succession. 

 Kaup also detected the presence of an upper premolar, 

 situated as a germ above the second deciduous grinder, in a 

 young specimen of M. longirostris, corroborating the inference 

 drawn by Cuvier from the Dax specimen of M. angustidens ; 

 but he considered this tooth as the normal successor of the 

 first milk molar, the second of the series being the tooth 

 which it specially replaces. Dr. Kaup, in the first instance, 

 took a peculiar view of the afiinities and systematic relations 

 of his most remarkable genus DinotheriuTn ; but he has since 

 come round to the opinion advanced by other observers, 

 that it was a true pachydermatous form,^ closely allied to 

 Mastodon. 



The discussion respecting Tetracaulodon, which had been 

 suspended in America, was renewed in England on the 

 occasion of Koch's public exhibition of the entire skeleton, 

 and other remains of the North American Mastodon, in 

 London, during 1841. The ingenious exhibitor contrived a 

 fanciful reconstruction of the skeleton inconsistent with the 

 principles of animal mechanics. The huge tusks, instead of 

 being placed with their points directed upwards, as in the 

 elephant, or downwards, as had been formerly suggested by 

 Mr. Rembrandt Peale,* were spread out horizontally with 

 diverging curves, so as to resemble two great sickles. Other 

 corresponding extravagancies were exhibited in the apposi- 

 tion of the limbs, and for the grotesque form so constructed, 

 Mr. Koch proposed a distinct generic place, under the desig- 



> Isis, 1832, p. 628. 

 ^ Ossemens Fossiles de Darmstadt, 

 1835, part iv. pp. 65-89. 



3 Akten der Urwelt, 1841. 



* Cuv. Oss. Foss. torn. i. p. 239. 



