DESCRIPTION OF PLATES. 463 



remains. The six posterior ridges have their fang elements confluent 

 into a continuous plate or shell, thus maintaining the elephantine 

 affinity indicated by the crown characters. The crown is very flat ; 

 the points are large and few in number, and there is no very distinct 

 mesial dividing line, but little cement. This magnificent specimen was 

 brought from Burmah by Col. Burney, and presented by him to the 

 British Museum (See antea, p. 114, and Plate V. of vol. ii.). 

 Length, 12-7 in. Width at middle, 4-5 in. 



Figs. 6 and 6 a. — Mastodon latidens ^ (Clifl;). Fragment of lower 

 jaw, left side, with last or third true molar. This is one of the most 

 enormous specimens ever seen, the greatest girth over the molar being 

 no less than 27'5 inches. There is one mental foramen ; no appear- 

 ance of tusk. The molar has five ridges and a double heel ; the points 

 are very large, and the discs of wear very broad ; the mesial line of 

 division is distinct ; there is no cement. The plane of wear in front 

 shelves from the inside out. There is a very similar specimen in the 

 Museum of the Asiatic Society of Bengal (See antea, p. 120). 



Extreme length of fragment, 16-2 in. Height of jaw at anterior end of 

 alveolus, 10-2 in. Greatest thickness, 6-8 in. Length of molar, 11-3 in. Greatest 

 ■width, 4-5 in. 



Plate XXXI. 

 Figs. 1 and 1 a. — Mastodon latidens. Upper milk molar. — B.M. 



Length, 27 in. "Width, 2-4 in. 

 Figs. 2 and 2 a. — M. latidens. Upper milk molar (third ?). — Cast in B.M. 



Length, 3-8 in. ■ Width, 26 in. 



Figs. 3 and 3 a. — M. latidens. Fragment of upper jaw, right side, 

 with two molars (third milk and first true ?). — B.M. 



Length of posterior molar, 5-6 in. Width, 2-9 in. Length of anterior molar, 

 3-7 in. Width, 2-6 in. 



Figs. 4 and 4 a. — M. latidens. Portion of palate, with two i;pper 

 molars left side B.M. 



Length of anterior tooth, 3-9 in. Width, 2-8 in. Length of posterior tooth, 

 4-2 in. Width, 3-4 in. 



Figs. 5 and 5 a. — M. latidens. Fragment of upper molar. — Cast in 

 B.M. 



Length of fragment, 3-4 in. Width, 42 in. 



Figs. 6 and 6 a. — M. latidens. Upper true molar, very perfect. — B.M, 

 Length, 8-5 in. Width, 4-5 in. 



Figs. 7 and 7 a. — M. latidens. Fragment of lower molar with fang 

 (See antea, p. 121). — B.M. 



Length, 5' in. Width, 3-3 in. Length of crown fang, 5-3 in. 



Figs. 8 and 8 a. — M. latidens. Lower molar well worn (See antea, 

 p. 121).— B.M. 



Length, 6-4 in. Width, 3-3 in. Height of crown fang, 6-4 in. 



Mastodon latidens, like the M. longirostris of Bppelsheim, presents a 

 Dinotherian type, in so far as the crowns of the molar teeth are con- 

 cerned; and in this respect it contrasts with M. Sivalensis and M. 

 Arvernensis, in which the molars have a hippopotamoid type. In M. 

 latidens the crown is broad, the mammillae are thicker in proportion 



' See note 1, page 461. 



