that it supports two pairs of points and one single point, like
the last lower molar tooth of the fossil jaw from Lot-et-Garonne,
described by Cuvier in the ‘Ossemens Fossiles,’ 1822, tom h i .
p. 404; and like that from the Puy en Velay, described in the
posthumous 8vo. edition of the same work, vol. v. p. 480, both
of which are referred by Cuvier to the genus Anthracotherium.
The last molar in the present fossil differs, however, from the
teeth above cited, in the height of the connecting ridge of the
anterior pair of points, and in the development of the fifth or
posterior point from the apex of the angular ridge connecting the
posterior pair of points.
From the closer resemblance which the fossil presents to the
true Lophiodons, it must be regarded as a member of the same
family of Tapiroid Pachyderms; indicating therein a distinct subgenus,
characterised by the want of parallelism of the two principal
transverse ridges, and the rudimental state of the posterior
talon in the last molar tooth of the lower jaw. The name
Coryphodon, which I have proposed for this suhgenus, is derived
from xopvtpri a point and Hovt a tooth, and is significative of the
development of the angles of the ridges into points.
A right canine tooth, obtained from the same eocene formation
as the foregoing molar, hut from a different locality in England, either
belongs to the same extinct genus of Pachyderm or indicates
another. The general proportions of this tooth, its degree of
curvature, and the relative length of the crown and the fang,
accord pretty closely with those of the canines of different species
of Lophiodon figured by Cuvier in the ‘ Ossemens Fossiles,’ 1822,
tom. n. pt. 1. pi. 10, figs. 312. & pi. 9, fig. 11. The crown
must have projected but a small distance beyond that of the
adjoining teeth, and have been quite concealed by the lips, as in
the Tapir, not forming a projecting tusk, and being shorter and
thicker than the canine of a carnivorous quadruped. Cuvier does
not give a figure of the transverse section of the crown of the
canine in any of his Lophiodons: that of the present tooth
is very characteristic, and resembles the transverse section of
the crown of the teeth of the great extinct reptile called
Pliosaurus; the outer surface being nearly flat, and the rest of
the crown so convex as to describe a semi-circle : a ridge of
enamel along each border of the flattened side separates it from
the convex side of the crown. This fossil tooth presents a peculiarity
which I have not before observed, or found described, in
having the crown defended by two layers of enamel: the outer
and thicker layer has a minutely wrinkled surface and terminates
near the base of the crown by a finely plicated border, extending
lower upon the posterior and outer than upon the anterior and inner
sides of the crown: the thin and smooth layer of the enamel
extends to and defines the base of the crown, the outer layer
being co-extensive with the inner one only at the two boundary
ridges, and the inner layer being extended further upon the tooth
at its anterior and inner sides. The length of this tooth must
have been three inches when entire; the circumference of the base
of the crown is two inches, nine lines. (1)
224. Dinotherium,.-^The most extraordinary of extinct Pachyderms
is that which Cuvier regarded as a gigantic Tapir, on
account of the character of the molar teeth, and which subsequent
discovery of the cranium and the enormous tusks of the lower jaw
(PI. 99, fig. 6) has proved to be a genus connecting the Tapiroid
with the proboscidian families of Pachyderms.
The permanent dentition of the genus Dinotherium is
T Inci. sors 0——0 ; cani. nes 0——0 ; premo,l ars 2——2 ; mo,l ars 8——3 -: = 22. 1—1 0—0 1 2—2 - 8 -3
the deciduous dentition was most probably:—
Incisors HI canines — ; molars — : = 16. 1—1 0—0 3—3
The first deciduous molar of the upper jaw has not yet been
detected; it is highly probable that such a tooth existed, and I
concur with Professor Kaup in regarding the two deciduous
molars in situ, on each side: of the fragment of the upper jaw of
the young Dinotherium which he has figured in Tab. 1, of his
‘ Ossemens Fossiles de Darmstadt’, as the second and third.
The crown of the second milk-molar supports two transverse
(1) History of British Fossil Mammalia, PI. 306, fig. 105.
R R