ELEPIiAS PRIMIGENIUS.—TRUE MOLARS. 103 



included in the space of 4^ inches. There is an abnormal character worth noting in the 

 jaw No. ^ (Woodcuts, figs. 12 and 26). The dental canal, which as a rule opens, as 

 has been stated, directly upwards in the Asiatic Elephant and in the Mammoth, faces 

 directly backwards in the above, thereby presenting an exception to a very general rule 

 as far as the Mammoth is concerned ; the jaw, moreover, shows an anomaly as regards 

 the corresponding levels of the mentary foramina ; the beak is also more horizontal than 

 usual (Woodcut, fig. 26, p. 139). 



Although the Ilford mandibles of the Mammoth above described belong to smaller 

 Elephants than equivalent remains from several other parts of England and elsewhere, and 

 in length and thickness of the jaw, height of the horizontal ramus, and length of the 

 molars, are conspicuously smaller than in the two mandibles of the recent species, it will 

 be observed that the rami diverge much more, the gutter is wider, and the distance 

 between the heels of the teeth greater in the Mammoth. With reference to the dis- 

 tinguishing characters of the mental region, horizontal and ascending rami, direction of 

 the diasterae, and other points to be again referred to when describing the mandible, 

 although the distinctions are well marked, I find that, as compared with the same parts in 

 the jaws of all other known species of the genus, the mandible of the Asiatic Elephant 

 is more closely related to the Mammoth than to any of them. 



To sura up the materials, it would appear that out of twenty upper and lower anterior 

 ante-penultimate molars one holds a formula of a? 9 cV, twelve of a' 12 x, three of a? 18 a;, 

 three oixl^ x, and one of .r 15 x. 



Affinities. — The points of difference between the first true molar of the Mammoth and 

 E. antiquus are usually well marked. The enamel, whether thick or thin, is never so 

 much crimped, and the absence of the central angulation and expansion, together with 

 the relative greater width to length, can scarcely fail in experienced hands to distinguish 

 a true molar from that of E. antiquus and E. NamacUcus. As to E. meridionalis, its massive 

 size, excessive development of cement, thicker enamel, and low ridge formula, will suffice 

 to establish a diagnosis. The Asiatic Elephant, with its narrower crown and densely 

 crimped enamel, make distinctive characters, which are common also to E. Armeniacus, 

 E. Columbia and E. Hysudricus,^ with which it deserves to be compared most carefully. 



The PerMltimaie or Second True Molar. 



The penultimate true molar, as with its predecessors, shows a progressive increase in 

 the number of its ridges, from the maximum ridge formula of the ante-penultimate to the 

 minimum number in the ultimate true molar; consequently nearly the same uncertainty 



1 Falconer, ' Pal. Mem.,' vol. ii, p. 220 and 24/, pi. x. 



2 ' F. A. Sival.,' pi. vii, figs. 2 and 10. E. Ilysudrkus holds x \2 x in its first true molar. 



