234 
DIPROTODON. 
of ribs, of a blade-bone, and of some of the long bones, 
together with a right heel-bone,—which there are grounds for 
believing belonged to the same animal. 
The various fragments of the lower jaw show that the 
Diprotodon possessed one incisor tooth and five molars in 
each ramus. The incisor is remarkable for its great size: it 
is very long, being deeply implanted in the jaw, and its direc¬ 
tion approaches the horizontal, but the extremity is slightly 
curved upwards. A section of this tooth presents a rounded 
outline, and gives a vertical diameter of one inch and a half, 
whilst the transverse measurement is nearly an inch. The 
apices of these incisors were bevelled off as in the incisors of a 
Rodent, and the resemblance to the cutting teeth of the 
Rodents is further manifested by the enamel being almost 
entirely confined to the outer surface of the tooth; the upper 
and the greater portion of the inner surface beiug destitute of 
enamel. The three anterior molar teeth exhibit a marked 
successive increase in size, whilst the posterior two arc nearly 
equal, and all these teeth are rooted, and with the exception 
of* the first, are longer than broad, and like the molars of the 
lower jaw of the Tapir, or those of the Kangaroo, the crown 
presents two elevated transverse ridges, hut these ridges arc 
still more elevated than in either of the animals just men¬ 
tioned: these principal ridges, or cusps, have a slightly 
elevated ridge miming downwards and inwards from then- 
on ter angle, which clearly represents the ridge similarly disposed 
in the Kangaroo’s molar tooth, though it is less developed in 
the Diprotodon, and here there is scarcely a trace of the lon¬ 
gitudinal ridge which joins the two principal cusps in the 
molar tooth of the Kangaroo. Besides the two principal 
cusps, the band of the tooth is developed into a strong ridge 
in front, and a still stronger one on the hinder part of the 
molar; in this respect differing from the molar tooth of the 
