36 BRITISH AND EUROPEAN FOSSIL MASTODONS. 



Sir Charles Lyell, in his 'Manual,' 1 gives a figure of Mr. 

 Wighani's tooth of the natural size, in which a very notable 

 character of the young molars is well brought out. The 

 enamel of the niaininillse is seen to be furrowed vertically by 

 numerous deep parallel grooves, presenting the appearance 

 of a reeded column or of a number of cords pressed close 

 together, and disposed around a thick central axis. The 

 shell of enamel shows as if it were composed of distinct 

 narrow pieces glued together. The same character is at- 

 tempted to be represented by b&c of fig. 7, PL XXXVL of the 

 ' Fauna Antiqua Sivalensis,' also of the natural size. It does 

 not occur in the corresponding young molars of M. (Tetralopho- 

 dori) longirostris. The enamel-surface in these is superficially 

 wrinkled and furrowed with numerous irregularities, without 

 however exhibiting the symmetrical fluting observable in the 

 Crag Mastodon. So conspicuous is this character, that I 

 believe that the young teeth of the two species could be 

 distinguished from each other by portions of their enamel 

 alone, occurring mixed in a collection. I would refer to a 

 figure given by Kaup of the dentition of a young Mastodon 

 longirostris in PL XVI. fig. 1 of his ' Ossemens Fossiles,' for 

 the comparison. It is of the natural size, and the last milk 

 molar may be contrasted with the corresponding tooth of the 

 Crag species figured by Sir Charles Lyell. It was this 

 character in the young teeth which chiefly led Croizet and 

 Jobert, 2 in 1828, to propose Mastodon Arvernensis as a distinct 

 species. They met with specimens in Auvergne, mostly of 

 very young animals, of both the upper and lower jaws, in 

 which the last milk molar was unworn ; and they were struck 

 with the remarkable complexity of the crown-ridges, com- 

 posed of a great number of small wart-like cones, separated 

 by the decurrent vertical grooves, which we have referred to. 

 But the indicated character was not accepted by Cuvier as 

 of sufficient importance to distinguish the species from his 

 too comprehensive Mastodon angustidens. 



Another fine specimen of the last upper milk molar, from 

 Mr. Pitch's collection, is figured in the ' British Fossil 

 Mammalia ' (fig. 100, p. 284). Like Mr. Wighani's specimen, 

 the crown is composed of four ridges and a talon, with the 

 same complexity of pattern, alternation of the flanking 

 tubercles, and interruption of the valleys. It is only necessary 

 to cite it here, as proving the constancy of the characters of 

 the Crag specimens. Prof. Owen describes this tooth as the 

 ' fourth upper molar ;' while he assigns a different position 

 and value to Mr. Wighani's specimen, considering the latter 



1 Manual of Element. G-eol. 5th edit. 

 (1855), p. 166. fig. 133. 



2 Croizet et Jobert, Oss. Eoss. du De- 

 part, du Puy-de-D6me (1828), p. 133. 



