239—58 
SIWALIK AND NARBADA PROBOSCIDIA. 
European species is laterally compressed, has a long tusked symphysis, and its in- 
ferior border bends suddenly upwards below the first molar. (E. A. S., PL XLV, 
fig. 10). 
Species 4 : Mastodon perimensis, Ealconer and Cautley. Pis. XL, XLI, figs. 1, 
3, 4, XLII, XLIII. 
History and specific characters. — The remains of a species of Mastodon obtained 
from Perim Island were referred by the authors of the “ Eauna Antiqua Sivalensis ” 
to a new species, under the name of Mastodon perimensis^ and figures of the cranium 
and of some of the molars are given in Plates XXXI, XXXVIII, XXXIX, and XL 
of that work, though no detailed description of the species was ever published. 
Various notes, however, on the teeth of this species will be found scattered through 
Dr. Ealconer’s papers, as collected in the “ Palaeontological Memoirs,” and figures 
of two molars are given on Plate IX of the first volume of that work. In the 
synopsis of the species of Mastodon and Elephant given on pages 14 and 15 of the 
second volume of the “ Palaeontological Memoirs,” Mastodon perimensis is classed 
among the Tetralophodons which have the columns of the transverse ridges arranged 
alternately, and the intervening valleys blocked; while on page 12 of the same 
volume, we find it stated by Dr. Ealconer that the molars of this species have a 
considerable quantity of cement in the valleys. The figures of the molars in the 
“ Eauna Antiqua Sivalensis ” show that they are characterized by the valleys being 
mainly transverse, but blocked in tlie middle by accessory columns, while one of the 
columns of each of the transverse ridges, when worn, presents a rudely trefoil-shaped 
dentine surface. In the “ Records of the Geological Survey of India,”^ I have 
mentioned the discovery of a mandible of this species in the Punjab, and have also 
shown that the species was provided with upper premolars, and that the male was 
provided with small cylindrical mandibular incisors. The teeth figured in the 
“ Eauna Antiqua Sivalensis” are in most instances more or less imperfect specimens, 
as is so very frequently the case with fossils from Perim Island, which have usually 
been subjected to a long course of washing and rolling on the sea-beach. The teeth 
of M. perimensis collected by Mr. Theobald in the Siwaliks of the Punjab, which 
form the subject of the present notice, are in far more perfect condition. The milk- 
molars of this species are unfortunately at present, with one exception, unknown, 
but specimens have been obtained of the whole of the series of true molars, and 
one specimen of the last upper premolar is known. In describing these teeth I shall 
take them in the order of their serial succession, 
T'irst upper milk-molar. — The small tooth represented in fig. 3 of Plate XLI 
was obtained by Mr. Theobald in the Siwaliks of the Punjab. Erom its size and 
shape, it is evidently the first upper milk-molar of a Mastodon, and from the dis- 
tinctness of the two ridges, in all probability of a tetralophodont species ; from the 
' Vol. XI, p. 71 ; Vol. XII, p. 45. 
