wmmmm 
mmmm 
ELEPHAS PRIMIGENIUS.—TRUE MOLARS. 
109 
By compounding the foregoing and other data it seems to me that the ridge-formula 
of the second true molar of the Mammoth exhibits a formula ranging from x 14 x to 
x 16 x (rarely), and in the lower jaw from a? 14 a? to x 18 x. Moreover, that the most 
usual formula in upper molars would seem to be x 15 x, and in lower x 16—17 x. The 
ratios in the latter being, out of twelve entire molars, as follows Two had a formula of 
x 14 x, two of a? 15 x, three of a? 16 a?, two of a? 17 a?, and two of a? 18 x. 
The range in equivalent teeth of E. Asiaticus is not, as far as I have been able to 
make out from many specimens, so great as in the Mammoth, and although as low a 
figure as fifteen plates, and even seventeen plates, with talons, may occur occasionally, the 
normal and very steady number of sixteen, besides accessory ridges, seems to prevail in 
that species. 
The E. Hysudricus , whose dental characters present several interesting comparisons 
with both of the preceding, shows in the approximation of its ridge-formula, as well as 
the disk patterns, certain affinities with them, but more especially with the Asiatic 
Elephant. 1 
In comparing the tooth of E. antiquus with that of the Mammoth, I have stated 
elsewhere" that the ridge-formula of the latter seldom averages less than x 16 x, being 
then unaware of the instances I have just pointed out, and resting on the data furnished 
by Palconer. I believe this number is not nearly so frequent, at all events in teeth from 
British strata, as the formulae x 14 a?and x 15 x, which seem tome about equally common 
to the second true molar in either jaw. Moreover, it appears to me extremely unlikely 
that any practised observer would confound entire specimens of the Mammoth’s second 
true molar with that of any of its congeners. Fragmentary specimens will always be 
puzzling, but a well-worn crown, with its high ridge-formula and characteristic sculpturing 
of the worn surface, can scarcely be mistaken for that of any species hitherto described. 
The Ultimate or Third True Molar. 
The ridge-formula of the last of the dental series in the Mammoth ranges from a? 18 a? 
to x 27 x, and probably individuals may be met with presenting a still higher number of 
plates. 
The characters of the last tooth are too patent to lead to mistakes in practised hands, 
admitting, as in all cases of other members of the series, it is perfectly entire and the 
crown sculpturing pronounced. 
Upper Molars .—The lowest expression of ridges which has come under my notice is 
shown in No. 47,122, B. M., in a tooth from “ river gravel at Kettering, Northampton.” 
This upper molar holds x 18 x in 10 X 4j inches, and eight ridges are contained in 4f 
inches. The plates are thin and there is faint crimping of the machaarides. 
Compare pi. vii, fig. 3, ‘F. A. Sival.,’ with fig. 4 of the same plate, erroneously stated as being 
the tooth of E. Hysudricus, whereas it belongs to JS. Asiaticus, ‘ Pal. Mem.,’ i, p. 428. 
2 ‘ Monograph,’ p. 30. 
15 
