SIWALIK NAEBADA PEOBOSCTBIA. 
91-272 
cuspsl Of two young skulls in the Indian Museum containing the third milk- and 
the first true molars, the first true molar in the one carries seven ridges and tAvo 
talons, and has a length of 5‘7, and a width of 2’6 inches, while in the other the 
corresponding tooth has eight ridges with a length of 6*5, and a width of 2'9 inches, 
A specimen of a skull from the Asiatic Society of Bengal, now in the Indian 
Museum, has seven ridges in the first true molar. It would appear, therefore, 
that while seven is the normal number of ridges in this tooth, this number may 
occasionally he increased to .eight. 
First lower true molm\ — Of the first lower true molar a worn specimen in the 
Indian Museum seems to have seven ridges, and has a length of 5‘2 inches, with 
a breadth of 2'8 inches ; a very similar specimen also carries the same number of 
ridges. A specimen of the first lower true molar of this species represented in 
fig. 4 of Plate XXV of the “ Pauna Antiqua Sivalensis” also has seven ridges 
and a hind-talon. As far, therefore, as is at present known, seven seems to he tlie 
constant number of ridges in this tooth. 
Second upper true molar. — A specimen of the second upper true molar repre- 
sented in fig. 5 of Plate XIX of the “ Eauna Antiqua Sivalensis” exhibits eight 
ridges and a front talon : another specimen in fig. 4 of the succeeding plate of 
the same work has also eight ridges, with fore-and-aft talons. A cranium described 
on page 41 (Xo. S. 4) of Dr. Ealconer’s “ Catalogue of the Eossil Vertehrata in the 
Museum of the Asiatic Society of Bengal,” and now in the collection of the Indian 
Museum, exhibits the first and second true molars, the latter of which has only 
seven ridges ; the penultimate tooth in the same skull has only six ridges, hut an 
anterior ridge may have disappeared in wearing. In the skull figured in fig, 2 of 
Plate XIX A of the “ Eauna Antiqua Sivalensis,” there are only seven ridges in the 
penultimate true molars. Other specimens of the second upper molar of S. msignis 
in the Indian Museum exhibit eight ridges. Eight may, therefore, he taken as 
the normal number of ridges in this tooth, with seven as an occasional variety. 
Second lower true molar. — Three perfect specimens of the second lower true 
molar of Stegodon msignis in the collection of the Indian Museum exliihit respect- 
ively, eight ridges and two talons. Two specimens of this tooth represented in figs. 4 
and 9 of Plate XX of the “ Eauna Antiqua Sivalensis’’. exhibit, respectively, nine 
and ten ridges. Another specimen figured in the same work has seven ridges 
(Plate XXA, fig. 2, S. ganesa)\ while yet another (Plate XXIV A, fig. 3) has up- 
wards of twelve ridges. The specimen drawn in Plate XXXVIII, fig. 2, of Clift’s 
memoir, has nine ridges and a large hind talon. Eight or nine may therefore he 
taken as the normal number of ridges in this tooth, with occasional variations from 
seven to twelve. 
Last true molars. — The number of ridges in the last upper true molar seems to 
vary from ten to eleven, and in the lower from eleven to thirteen. 
1 The tooth figured in Plate XXIV, fig. 1, of the Fauna Antiqua Sivalensis as the first true molar of S. ganesu. 
has only six very broad ridges, with few cusps, and probably belongs to S, bomhifrons. 
