4 FAUNA ANTIQUA SIVALENSIS. 
tion of the intermediate type of a proboscidean molar tooth, from which 
those of the other species diverge in opposite directions. It belongs to 
the Mastodon Elephantoides of Clift. The dark granulated shade 
below the portion of the ivory nucleus sustaining the five posterior 
ridges indicates the hollow of their common fang, which in the fossil is 
occupied by a core of sandstone.—B.M. 
Length of tooth, 10°3 in. 
Fig. 6 6.—Elephas insignis. Vertical section of anterior portion of 
adult tooth of lower jaw. The two front ridges only have been touched 
by wear. The ivory, enamel, and cement present the same characters 
as in the upper molar, but the common curve of the crown is slightly 
concave instead of convex. The posterior part of the basal portion of the 
pulp nucleus has not completed the stage of calcification, its place being 
occupied by a nest of calcareous crystals. The figure also shows two 
ridges of the preceding molar, with their common fang implanted in ~ 
the lower jaw.—B.M. 
PATE ile 
Fig. 7 a.—Elephas Ganesa, a fossil Indian species. Vertical section 
of last upper molar. The crown consists of ten principal ridges, with a 
subordinate talon ridge in front and behind. The anterior seven ridges 
have their summits worn. A small portion is broken off at the anterior 
end. The disposition and relative proportions of the ivory, enamel, 
and cement bear the closest resemblance to those of the corresponding 
tooth of #. insignis, and the number of ridges agrees. In fact, there are 
no good characters by which the teeth of these two species can be 
satisfactorily distinguished, although the crania are so remarkably 
different—B.M. 
Length of tooth, 9:25 in. 
Fig. 7 b.—Elephas Ganesa. Vertical section of posterior molar of 
lower jaw. A small portion of the anterior end of the crown has been 
broken off, but the presence of the anterior fang proves that the section 
includes the whole length of the tooth, except the first ridge, the 
posterior end being entire. It appears to have consisted of eight prin- 
cipal ridges, with a talon ridge behind, and a subordinate ridge in front. 
Five of the ridges have been in use, the anterior two being worn down 
close to the common base of ivory ; the three last ridges are entire. It 
bears a close resemblance to the corresponding inferior tooth of Z. 
msignis in the form of the ridges, thickness of enamel, and proportion 
of cement.—B.M. 
Fig. 8.— Mastodon latidens (Clift). Vertical section of two last 
molars of upper jaw. The specimen of which the section was made 
was formerly in the collection of the Geological Society, and is figured in 
Clift’s memoir (Plate XX XVII. fig. 1). The last tooth shows five prin- 
cipal ridges with a posterior talon ridge and a subordinate ridge in front. 
The ridges are transverse and divided by a longitudinal cleft into two 
pairs of principal points without intermediate mammille in the hollows. 
The enamel is very thick and the cement is reduced to a thin layer, 
only observable in the bottom of the hollows. The ivory lobes resemble 
those of . Ganesa, but are less elevated, with a broader base. The 
anterior tooth had been a long time in use, and the ridges are nearly all 
