256 BULLETIN NO. VII. —~ 
first, the rwmen into which the food is taken as it iseaten. The 
net is a shallow sack so placed that the coarse unmasticated 
food is directed into the rumen, while after it is regurgitated 
and finely comminuted it passes through a groove into the leaf 
stomach and finally into the fourth compartment where the 
gastric juice is freely mingled and the digestion proper begins. 
Intelligence is not great, as a rule in the group, the brain 
being small and the organs of sense only moderately developed. 
In some species which are little able to protect themselves, the 
senses of sight and smell are highly developed and caution and 
powers of flight supply the place of craft and other mental en- 
dowments. The habits are comparatively uniform and are 
chiefly interesting on account of the various ways in which they 
are made to minister to man’s necessities. 
It is almost as difficult to understand how civilized nations 
would do without kine, sheep, goats, swine, etc., as to imagine 
a Laplander living without the reindeer or a desert Arab with- 
out the camel. I need not refer to the sport furnished by the 
various deer and antelopes the world over. 
The placenta is diffuse and the mamme are ventral or in- 
guinal. 
The swine constitute a very old group and, like many another 
old family, have preserved tolerably connected records from 
the earliest times. Even in the Eocene period we find swine 
with two hoofs (Entelodon, Cherotherium,etc.,) while in the mid 
dle Miocene members of the modern genus Sus are encountered 
In the Eocene gypsum beds of Montmartre are four-toed swine 
of the genera Cheropotamus and Hyopotamus. In the Miocene an 
offshoot furnished origin to the comparatively recent family of 
the Hippopotamide. The genus Merycopotamus, remains of which 
are found in India, afforded a transition to true river-horses 
with six incisors. During the quarternary the various forms, 
some of which were hardly larger than a hog, others larger 
than the leviathan of the Nile, disported themselves in the 
shallows of the inland seas of Europe as far as Ireland. A 
colder period drove them across what is now the Mediterran- 
ean and from similar causes they became extinct in India also. 
At present, the two species are strictly confined to the con- 
tinent of Africa. 
Two distinct geneological trees are required in the study of 
the swine proper. In America there seems never to have ex- 
isted any animals of the genera Sus, Porcus, or Hippopotamus 
or even of related genera. 
