ry 
1872.] 543 [Cope. 
crescent of the tooth-crown to meet at the apex, in the molars proper 5 
second, the presence of two lobed premolars only, the three lobed found 
n Bathmodon not being represented in any series. The first character 
appears to me to be of generic importance, hence the name applied to it 
at the head of this article. It may yet prove to be Loxolophodon, as no 
generic character distinguishes the inferior molars of the two. It remains 
however, to determine whether that name applies to Bathmodon, ora 
genus different from it, as the present. In the meantime the new species 
may be called Metalophodon armatus. It is as large as the Indian 
Rhinoceros, or perhaps larger. 
The incisors are well developed, those of the premaxillary subequal in 
size. The crown has a convex cutting edge and flat inner face. The 
outer face is convex. In some the inner face is more concave, and is 
bounded by a cingulum next the root. 
The premolars present a single external crescent of acuminate ontline, 
and a smaller, more transverse one, within. A cingulum bounds the 
crown fore and aft, but is wanting at both base and apex of the trian- 
gular base. Inthe more posterior the crescent is more open, and the 
crown less transverse. 
Tho molars present an increase in transverse extent of the external 
crescent, and the interior one is wanting. In the posterior two the 
anterior ridge curves round at the apex, but issseparated by a consider- 
able interruption from the posterior. The latter is shortened, and 
terminates externally in a conic tubercle, which approaches the outer 
extremity of the anterior ridge. In the last molar the posterior ridge 
is shorter, nearly straight, and terminating in a cone at each extremity. 
The canine is damaged, but was of large size, amounting in one or 
the other of the jaws to a tusk. The probably superior is compressed, 
with acute edges. The inner face gently convex, the outer more strongly 
so, with an acute ridge on its anterior convexity, inclosing an open 
groove, with the interior cutting edge. This surface of the dentine when 
exposed has a transversely wrinkled character, but no trace of engine- 
turning in the fractures. 
In the mandible, premolar and molar teeth are recognizable; the 
character of the incisors remaining uncertain. As usual in ungulates, 
they possess a relatively smaller transverse diameter than do the cor- 
responding teeth of the maxillary. They change very materially in 
form from the front to the terminus of the series, and in connection 
with the superior molars, are very instructive as to the genetic connec- 
tion of different types of dentition. 
The pecularity of the premolars consists in the fact that besides the 
single external crescent exhibited by those of the upper jaw, they have 
a rudimental second one in the position it should oceupy in correspond- 
ing teeth of Palwosyops. The inner border of the crown is convex, and 
extends from apex to apex of the crescents. There are no cingula to 
these teeth. The rudimental crescent diminishes anteriorly, its angle 
