219—38 
SIWALIK AND NARBADA PROBOSCIDIA. 
owing to tlie sandy matrix having become mingled with the enamel. The tooth is in 
germ, and has a convex crown surface, carrying four transverse ridges, and fore-and- 
aft talons. The anterior talon consists of a semi-circular ledge attached to the first 
ridge. The true ridges and the hind- talon correspond exactly in form with those 
of the corresponding lower molar represented in fig. 2 of Plate XXXIV : they 
are tall, placed somewhat alternately, and divided by a deep longitudinal cleft. The 
accessory tubercles appear to he arransred as in Falconer’s specimens of the earlier 
upper molars ; the valleys are completely blocked by outlying tubercles, and also 
contain a comparatively large quantity of cement. The length of the specimen is 
7*7 inches, its greatest width 3*8 inches, and the height of the second ridge 3*3 
inches. 
First loioer true molar . — The imperfect small tooth represented in fig. 1 of Plate 
XXXV is implanted in a fragment of the right ramus of a mandible, and, like 
the preceding specimens, was collected by Mr. Theobald in the Siwaliks of the 
Punjab. Prom its small size, this tooth must evidently he either the last milk-molar, 
or the first true molar, and from carrying only three transverse ridges, it must 
evidently belong to a trilophodont Mastodon. As the tooth is only slightly smaller 
than the second lower true molar represented in fig. 1 of Plate XXXIV, it is 
probable that it is the first true molar. The tooth is entirely unworn, and has lost 
the inner column of the first ridge. The posterior extremity of the specimen is 
slightly narrower than the anterior ; and there seems to have been a very small 
mterior talon, judging from the fragment remaining on the outer column, and there 
is a very distinct hind-talon, of a much lower elevation than the third ridge. The 
ridges are all of great relative height, and are divided mesially by a cleft along the 
antero-posterior axis of the tooth ; each ridge is slightly convex anteriorly, and con- 
cave posteriorly. Prom either side of the outer column of each ridge accessory 
columns or tubercles project into the transverse valleys, completely blocking them^ 
nearly up to the summits of the ridges. Cement occurs in some quantity in the 
valleys. The length of this tooth is 4*2 inches, its greatest width 2*3 inches, and 
the height of the outer column of the first ridge 2 inches. 
In being furnished with cement, as well as in the great relative height of the 
transverse ridges, this tooth agrees with the penultimate lower molar of M. pandionis 
represented in fig. 1 of Plate XXXIV. The accessory tubercles or columns are, 
however, less complex, and the ridges are placed less alternately than in the last 
lower molar represented in fig. 2 of the last-named plate. Now, we have already 
seen that the accessory columns are less developed in the second lower molar than in 
the upper molars, and it appears from the present specimen that these tubercles 
are still less developed in the earlier lower molars. 
The present specimen is readily distinguished from the corresponding tooth of 
the other Indian Trilopliodon [M. falconeri, Plate XXXIII, fig. 3) by its general 
shape, by the ridges being much higher (2 inches in place of 1*4 inches), by the 
valleys being blocked to a greater extent, and by the presence of cement. 
