THE ODD-TOED UNQtJLATES. 
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the Holy Land and Arabia, thought to be the coney re- 
ferred to in the Bible, is the only genus. 
Order 9. Toxodontia. — Of this group, of which no spe- 
cies are now living, the types are Toxodon and Nesodon. 
They are placed by many autliors among the odd-toed 
Ungulates, not far from the tapirs. Their incisors were 
I or Toxodon in its skull bore some resemblance to the 
Sirenians, and in the teeth were in certain respects like the 
Edentates. The species lived in South America during 
the early Tertiary Period. 
Order 10. Ungulata, — The larger proportion of mammals 
belong to this interesting order, which comprises nearly all 
those species of mammals useful to man, such as the ox, 
camel, pig, deer, and horse. They are, in general, charac- 
terized by walking, so to speak, on their toes, each toe 
being at the end encased in a horny hoof; not more than 
four toes being completely developed on a foot. The teeth 
are usually well developed, with six incisors in each jaw, 
but these are often, especially in the upper jaw, less in 
number or entirely absent, as in the sheep, deer, and ox. 
The collar-bone is absent. The brain still remains small 
compared with the bulk of tlie skull, and the intestinal 
canal is of unusual length compared with that of animals 
of the previous orders. 
The Ungulates have been divided by Ov/en into two sub- 
orders, according to the odd number of toes {Perissodartyla) 
or even number {Artiodactyla), In the odd-toed Ungu- 
lates (Perissodactyles) there may be three toes on each foot, 
as in the rhinoceros, or one, as in the horse; while in the 
even-toed Ungulates (Artiodactyles) there maybe four toes 
(Rippopotamiis), or two, as in the giraffe, or two functional 
and two rudimental, as in the ox and deer, i.e., most Kumi- 
nants. T'he more generalized existing form of Ungulates 
is the tapir; the most specialized type is the horse, with its 
single toe on each limb. A large number of extinct Ter- 
tiary Ungulates in the Western States and Territories, and 
the Tertiary basins of Paris and London, more or less allied 
