170 



697- A cast of a molar tooth, the third (second of the permanent series) of the 

 lower jaw of the Mastodon angustidens, Cuv. Its crown supports three 

 pairs of mastoid tuhercles, an anterior hasal ridge and a posterior bitu- 

 berculate talon ; a small tubercle is developed at the middle of each of 

 the valleys between the larger pairs of tubercles. The original of this 

 cast was transmitted from Saxony by Professor Hugo of Gottingen to 

 Bernard de Jussieu. Cuvier has figured it in the ' Ossemens Fossiles,' 

 1821, torn. i. pi. 11. fig. 11, and has noticed it at p. 267, as being appa- 

 rently too small to be referred to any of the species of Mastodon which 

 he had described. He points out its resemblance to the molars of the 

 Mastodon giganteus, which is figured in 'PI. III. fig. 4, Grande Masto- 

 donte': these are, however, the fourth and the fifth molar, or the third 

 and fourth of the permanent series, and the tooth of the Mastodon gi- 

 ganteus, which corresponds in size with the present specimen, is the 

 last of the three molars in situ in the jaw of the younger animal with 

 tusks, No. 705, the first and second of these molars forming the deci- 

 duous series and being replaced vertically by a single molar, which is the 

 first of the permanent series. Presented by Baron Cuvier. 



698. A cast of the fourth molar tooth (the third of the permanent series) of 

 the lower jaw of the Mastodon angustidens, Cuv. The original was dis- 

 covered in the tertiary strata of Simorre. Reaumur has figured a frag- 

 ment of a fossil molar of the same Mastodon in illustration of his 

 memoir on the Turquoise mines at Simorre in the ' Memoires de l'Acad. 

 des Sciences, 1715.' Daubenton notices the fossil Mastodont molars 

 from the same locality as " dents petrifies ayant des rapports avec celles 

 de 1'Hippopotame." Cuvier, who first determined the true nature and 

 relations of these fossil teeth of the Mastodon, commences his description 

 of them with the original of the present cast, loc. cit., p. 255. pi. 1. fig. 4. 

 The crown supported three pairs of mastoid tubercles (not six pairs, as 

 Cuvier describes, evidently by an error of press) : those of the first pair 

 have been worn down by mastication to their common dentinal base, which 

 presents the form of a quadrilobate disc : a line of enamel still divides 

 the contiguous bases of the second pair of tubercles : a little of the 

 enamel has been worn from the summits of the posterior pair ; these are 



