MASTODON ARVERNENSIS. 31 



Of the last true molar of tlie lower jaw, no good entire spe- 

 cimen, so far as I am aware, has yet been published as having 

 been yielded by the English Crag. But in the Museum of 

 the Geological Society, there is a cast of a very fine specimen 

 of this tooth from the left side of the lower jaw, which, 

 according to the label on the cast, was found in the Crag of 

 Suffolk (see PI. IV. figs. 3, 4). It is a nearly unworn germ, 

 measuring about 8^ inches long, by 3 inches in width in 

 front, without fangs, and the anterior ridge alone being 

 slightly touched by wear. It is composed of five ridges and a 

 talon of two mammillae. The anterior ridge shows two pairs 

 of mammillse ; the next four ridges present only two large 

 conical mammillae each, which converge rapidly towards the 

 summit of the crown, and are disposed in an alternate man- 

 ner. One or more large accessory mammillae are interposed 

 between the ridges, blocking up valleys in the manner 

 described as characteristic of the species, and the ridges are 

 inclined with a slope, which increases successively backwards. 

 The talon appears to have been composed of a pair of points, 

 one of which is mutilated on the inner side, and a small 

 portion of the back end of the tooth is wanting. The slope 

 of the posterior ridges is so pronounced as to approach nearly 

 to the character of ' imbrication.' In this respect the spe- 

 cimen closely resembles the Val d'Arno molar figured by 

 Cuvier (Divers Mastodontes, PL IV. fig. 7), which he describes 

 as the last of the upper jaw ; l but it would seem, from the 

 form and contour, to be an entire germ of the last inferior 

 molar, and, in our opinion, of the same species as the Crag 

 Mastodon, namely, M. (Tetraloph.) Arvemensis. 



A fragment composing the posterior half of the lasf" 

 inferior true molar has been noticed and figured by Mr. S. 

 Woodward. 2 It is composed of seven prominent conical 

 mammillae, disposed in three ridges, which contract very 

 much behind, and terminate in an odd talon-tubercle. 

 These tubercles form two lines, an outer and an inner, and 

 they are placed in regular alternation with each other. A 

 corresponding fragment, of which there is a cast in the 

 Geological Society's Museum, is represented by PI. XXXVII. 

 figs. 9 & 9 a of the ' Fauna Antiqua Sivalensis.' The mammillae, 

 in this case also, form two alternate rows, each ridge being 

 composed of a pair of points. 3 



The finest detached specimen of the Crag species that I 

 have anywhere seen is a last lower molar, left side, found 

 below the citadel of Montpellier, and which has been figured 



1 Oss. Foss. 4to edit. torn. i. p. 2.58. 



s Mag. of Nat. Hist. (1836), vol. ix. p. 152, fig. 22. 



3 See vol. i. p. 470.— [Ed.] 



