440 ZOOLOGY. 
hind ones, all of them terminated by a very small, thin, and rounded hoof, 
except the internal posterior, which is armed with a hooked and oblique 
nail; the upper lip is cleft ; the snout and ears are short; the body densely 
covered with hair; and the tail reduced to a mere tubercle. One species 
inhabits the Cape of Good Hope; another, H. syriacus (pl. 111, fig. 2), is 
peculiar to Asia. 
Fam. 7. Suipa. In the actual fauna, this family is characterized by a 
fluctuation in the proportional numbers of the teeth, and by four toes to 
each foot, by which it differs at once from Anoplotheride, with which it 
would seem to bear some affinity. The number of the molars varies from 
three to seven; the canines are always distinctly developed ; and the 
incisors may either be absent, or six and less may exist, situated more or 
less horizontally in the jaw. The two central toes alone touch the bottom 
with their three-sided pyramidal hoof; the other toes are much developed, 
as posterior claws provided with hoofs. The nasal bones elongate forward, 
and terminate by a proboscis-like nose, fitted for digging. The structure of 
the skeleton is more clumsy than in Anoplotherium, from which the Suide 
are always distinguished by a shorter stature. The living genera of this 
family contain but four species, and are distributed all over the surface of 
the globe, within the temperate and torrid zones. 
The genus Adapis, from the oldest tertiary beds, is considered by some. 
as belonging to Anoplotheride, by others to Suide. There are four sharp 
and oblique incisors above, and four below; behind these, and on each side, 
a stout and prominent canine, straight in the upper jaw, oblique and curved 
forwards in the lower; the upper molars, seven in number, are variable in 
form, as also the lower ones, the number of which could not be ascertained, 
from want of complete jaws. We know but one single species of this genus 
(A. parisiensis), from the eocene of Montmartre. 
The genus Hyotherium is not yet sufficiently characterized. Its remains 
were found in Central Europe, and indicate an animal of the suiline family, 
resembling very much the babiroussa now living in the Indian Archipelago. 
The number of the incisors is not known; the molars, it is supposed, were 
six on each side of each jaw. Five species are already described, one of 
' which had first been referred to the following genus. 
The genus Cheropotamus, therefore, must have some close affinities with 
Hyotherium, from which it differs in the structure of the molars. There 
are on each side seven above, and six below, of these teeth, intermediate 
between those of the peccaries and hippopotamus. Several species have been 
distinguished ; one from Paris, another from Switzerland, and a third from 
Spain. Undescribed fragments are known from the south of France and 
Turkey. 
The genus Protocherus appears to be an American form, as the only 
species known was found in Illinois. The canines resemble those of 
Cheropotamus, but differ from it in having no accessory tubercles on the 
molars. 
The genus Hyracotherium, from the London clay (eocene), is very nearly 
allied to Cheropotamus, by its dentition. The four anterior molars are 
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