SIWALIK AND NARBADA PROBOSCIDIA. 87—268 
Species 3 : Stegodon insignis, Palconer & Cautley. Plates XLV, fig. 4, XLVI, 
figs. 2 & 4. 
Synonym ; (?) S. orientalis, Owen. 
B-istory. — The first figured tooth of this species seems to he the specimen ob- 
tained from Ava, and figured by Mr. Clift in the “ Transactions of the Geological 
Society of London,”^ under the name of Mastodon elephantoides. Dr. Palconer 
subsequently showed ^ that the latter name really comprehended more than one 
species, and gave to the teeth with a high ridge-formula the name of Elephas {Ste- 
godon) insignis. Several skulls and a large series of teeth appear under that name 
in the “ Pauna Antiqua Sivalensis.” In the same work a considerable number of 
teeth also appear under the name of Elephas (Stegodon) ganesa : these latter teeth, 
however, cannot he distinguished from those named Stegodon insignis, and as we 
shall see subsequently,* it is only the adult skulls of these two very closely allied 
species that can he distinguished. The molars of Stegodon insignis also hear a very 
close resemblance to those of S. bomhifrons, hut are distinguished by a generally 
higher ridge-formula, and by the ridges being narrower and taller, as well as by the 
greater amount of cement which is usually present on them. Dr. Palconer^ consi- 
ders that the following formula represents the average number of the ridges of the 
molars of this species, though he remarks that there is a greater tendency to varia- 
tion in this respect than there is among the true Mastodons. Dr. Palconer’s formula 
is as follows: — 
Milk-molars, True molars. 
2-t-5-l-7 7-1-8 -h (10-11) 
2 + 54-7 7 + (8—9) + (11—13) 
W e shall subsequently see that this formula only requires very slight alteration 
as far as our present knowledge goes. As a very large series of the teeth of this 
species are figured in the “Pauna Antiqua Sivalensis,” I have only thought it 
necessary in this memoir to figure a few specimens of the milk-molar dentition, 
which exhibit well the general dental characters of the species, as distinguished 
from S. bomhifrons. 
First milk-molars. — Of the first milk-molars of Stegodon insignis I know of no 
perfect specimens, though a fragment of the upper tooth is attached to the young 
maxilla represented in Plate XIX, fig. 1, of the “ Pauna Antiqua Sivalensis.” 
Second upper milk-molar. — Of the second upper milk-molar of this species two 
specimens are represented in the “Pauna Antiqua Sivalensis;” one in fig. 1 of 
Plate XIX and the other in fig. 3 of Plate XXIX (misnamed in plate S. bombi- 
frons). The first of these teeth is complete and well worn ; it exhibits five complete 
ridges, in front a large talon or incomplete ridge, and behind a small talon. The 
* Ser. 2, Vol. II, PI. XXXVIII, fig. 2. 
2 Pal. Mem., Vol. II, p. 85. 
^ Ibid., p. 86. 
