ELEPHANTIDjE. 29 



M. pyrenaicus is a variety in which the accessory columns of the 

 molars are less developed, thereby indicating a transition towards 

 M. turicensis. This is the smallest and one of the most generalized 

 species. The upper incisors are furnished with an enamel-band ; 

 the mandibular symphysis is longer than in any other species, is 

 somewhat deflected, and carries large incisors, which have a pyri- 

 form basal section : the mandibular rami are laterally compressed. 

 The cheek-teeth are characterized by their extreme narrowness ; 

 their ridges are divided into inner and outer columns, which have a 

 tendency to an alternate arrangement, and the valleys are always 

 blocked by accessory columns, the development of which varies 

 considerably in different individuals. The inferior border of the 

 mandibular ramus is nearly straight, and the incisive alveoli are 

 parallel. One column of each of the earlier ridges wears into a 

 more or less complete trefoil: the "intermediate" lower molars 

 have a small anterior and a large posterior talon, the latter usually 

 having two distinct columns ; there is a certain amount of variation 

 in the form of the third true molar. A section of m. 1 is shown in 

 the accompanying woodcut (fig. 4). 



Mastodon angustidens. Vertical longitudinal section of the first lower true 

 molar ; from the Middle Miocene of Simorre. |. b, enamel ; c, den- 

 tine. 



Hob. Europe, N.W. frontier of India, and (?) North America. In 

 Europe 1 the species occurs in France, Switzerland, Bavaria, Bohemia, 

 Austria-Hungary, and Styria. In Eastern Europe it occurs in the 

 Middle Miocene, in Western Europe in the Sarmatian stage of the 

 same, and in Asia in the Upper Miocene or Lower Pliocene. The 

 Asiatic form 2 , which has been distinguished as var. palceindicus, 

 presents a somewhat greater development of the accessory columns ; 



1 See Vaek, Abh. k.-k. geol. Eeichs. vol. vii. pt. 4, pp. 23-25 (1877). 



2 Palffiontologia Indica (Mem. Geol. Surv. Ind.), ser. 10, vol. iii. pp. 19-29, 

 pis. iv., v. (1884). 



