ELEPHANTID-E. 25 



17198. The axis vertebra; from Missouri. Purchased. About 1844. 

 17881. A dorsal vertebra ; from Missouri. Purchased. About 1844. 

 17884. A dorsal vertebra ; from Missouri. Purchased. About 1844. 



17205, 17248. The neural spines of two early dorsal vertebrae ; 



from Missouri. Purchased. About 1844. 



17206. A lumbar vertebra ; from Missouri. 



Purchased. About 1844. 



41661. A lumbar vertebra ; from " Big-Bone-Lick." 



Toulmin-Smith Collection. Purchased, 1869. 



Mastodon borsoni, Hays 1 . 



Syn. Mastodon buffonis, Pomel 2 . 



Mastodon viryatidens, Meyer 3 . 



The mandibular symphysis is comparatively short, and is fre- 

 quently furnished with a pair of small incisors (see Lortet and 

 Chantre, Arch. Mus. Lyon, vol. ii. pi. xvi. fig. 1 [1878]), but in 

 other specimens appears edentulous (ibid. pi. xii. fig. 3) ; the ridges 

 and valleys of the molars run straight across the crown, the bases of 

 the valleys being partially blocked, and one half of each ridge 

 wearing into a more or less complete trefoil. The ciDgulum is con- 

 tinuous with the talons. The molars present a great resemblance 

 to those of M. amcricanus and M. turicensis, but are distinguished 

 from those of the latter by their generally superior size, greater 

 breadth, lower ridges 4 , general flatness, and the smaller cingulum 

 on the inner side of those of the upper jaw. It is probable that the 

 species is a more specialized branch of the stock of M. turicensis. 



Hab. Europe. The species was originally described from the 

 Lower Pliocene (Astien) of Asti in Piedmont, and has been sub- 

 sequently recorded by Vacek (Abh. k.-k. geol. Reichs. vol. vii. pt. 4, 

 pp. 6-11 [1877]) from the Lower Pliocene (Congerian) of Austria- 

 Hungary, by Lortet and Chantre (Arch. Mus. Lyon, vol. ii. p. 306 

 [1878]) from the Upper Pliocene of the south of France, and by 

 Forsyth-Major (Quart. Journ. Geol. Soc. vol. xli. p. 2 [1885]) from the 



1 Trans. Amer. Phil. Soc. ser. 2, vol. iy. p. 334 (1834). 



2 Bull. Soc. Geol. France, se>. 2, vol. v. p. 258 (1848). 



3 ' Palseontographica,' vol. xvii. p. 61 (1867). See Vacek, Abh. L-k. geol. 

 Eeichs. vol. vii. pt. 4, p. 7 (1877). 



4 Lankester, in describing teeth from the Red Crag, Quart. Journ. Geol. Soc. 

 vol. xxvi. p. 609 (1870), reverses these characters. 



