700 The American Naturalist. [August, 
tive form of the Halitheriidae known is the genus Dioplotherium 
Cope, with two superior incisors. D. manigaultü is a large 
species which was found near Charleston, S. Carolina, by Dr. G. 
Manigault of that place (Plate XXV). The first incisor lacks the 
distal expansion of that of Halitherium. The molars are unknown. 
Another and still more remarkable form has been discovered 
in the phosphatic deposits of South Carolina. This is the’ genus 
Anoplonassa Cope, in which the symphysis of one of the jaws is 
much elongated, is semi-cylindrical, and is not decurved as in the 
other members of the family. The premolar and molar teeth 
are shed at maturity, leaving indistinct traces, except, perhaps, the 
anterior incisor, which is represented by a large, shallow alveolus, 
and is perhaps not shed (Fig. 2). The muzzle is adapted to 
egit 
FIG. 2.—Anoplonassa forcipata Cope; one-fourth natural size. Original; from South 
Carolina. 
being inserted deep into mud in order to draw thence mollusca 
or other kinds of food. But one species is known, the Axoplo- 
nassa forcipata Cope. It is by no means certain that it belongs 
here, and it may be a Cetacean. 
The Manatip& are remarkable for the number of their molars. 
In the genus Manatus there are eight in the permanent dentition, 
and a ninth anterior tooth, which is early shed. "These molars 
are all alike, and with two transverse crests in the upper jaw and 
three in the lower. There is a minute incisor in the upper jaw, 
which is shed early. Besides the three living species of Mana- 
tus but few extinct species are known. Teeth resembling those 
of the Floridan species have been found in the Charleston de- 
posits, and have been named by Leidy M. fossis. A form 
from the Eocene of Egypt has been named by Owen EZotherium 
egyptiacum. Filhol does not distinguish the molars from those of 
Manatus as to their structure, but their number is unknown. 
