ELEPHAS ANTIQUUS.—RIDGE FORMULAE. 
47 
It can never in the future be the interest of the philosophical naturalist to create new 
species from a few minor characters. It seems to me, therefore, in order to realise the 
varying features in dental elements of Proboscidians, that strict cognizance should be taken 
of talons and the like in computing the ridge formula, which varies in every member of 
the series, not only in the recent, but in all known fossil Elephants; at all events, 
wherever sufficient materials have been obtained. It need scarcely be observed that the 
following ridge formulae are provisional and liable to extension in accordance with future 
discoveries. 
1. From the foregoing details it seems to me that the ridge formula of Elephas 
antiquus, as far as British specimens in particular demonstrate, is, talons included, in 
upper and lower jaws, as follows : 
Milk Molars. True Molars. 
_ _ _A__A-^ 
I. II. III. IV. V. VI. 
x2x — * 3 * * 5 * — * 7 x x 9 * — *10* x 9 x — x 12 x x \2x — x 13a *15*— x 20 x. 
x‘dx—1 *6*— *8* x 9 x — sella; x ll x— *12* *12* —*13* *16*— *19*. 
2. The ridge formulae of the Mammoth and Asiatic Elephant according to Falconer 
are the same if anything, there is also a greater range in the former than in E. antiquus, 
the ultimate molar varying in number from x 19 x to x 27 x. The lowest number of 
ridges in the last molar of the Mammoth, according to Falconer, is stated to be x 24 x, 
but Mr. Davies in the describing and naming of the valuable materials collected by Sir 
Antonio Brady, F.G.S., in the Ilford deposits, records entire ultimate molars of the 
Mammoth containing nineteen plates and two talons? consequently, if the extremes in the 
Elephas antiquus and E. primigenius meet, with the limitation in the lowest number of 
ridges of the last true molar as just indicated, the ridge formula of the Mammoth as 
given by Falconer will stand as follows: 
Milk Molars. 
I -*-'i 
I. II. III. 
x\x •—? x8x —•? x 12 x —? 
x4x — ? *8*— F x 12 x — ? 
True Molars. 
--- A - 
IV. V. VI. 
xl2x — x 14 x *16*— *18* *19* — *24*. 
*12*—*14* *16* — *18* *19* — *28*. 
3. The dental formula in the African Elephant appears to vary much, but it seem¬ 
ingly never attains to the number of ridges in true molars that is seen in any of the 
three preceding species. According to Blainville, Owen, and Falconer, none of whom 
give exactly the same formula, supposing they have not represented more than the 
exact number of ridges, including talons, it stands thus: 
1 ‘ Pal. Mem.,’ vol. ii, p. 157, and footnote, p. 236. 
2 ‘ Catalogue of Vertebrata for Ilford,’ p. 3. 
