44 Organs of the Animal Body : their Forms and Uses. 
function, it will be instructive to trace a portion of food from 
the mouth into the blood stream, which will carry it all over 
the system. 
Food is first grasped by the lips, or teeth, or both, and 
broken or ground up, mixed with the saliva, which softens it, 
besides setting up a fermentation which ends in the change of 
starch into grape sugar. The softened and altered food is 
swallowed, and in the stomach further changes go on ; the 
albuminoids are there changed into more soluble compounds 
(peptones), which pass easily through the membrane which 
forms the walls of the minute vessels. From the stomach the 
food passes into the first intestine, and is mixed with the bile 
and pancreatic fluid, which cause further changes. The bile 
prevents too rapid decomposition, and also promotes the 
absorption of fat, and helps to dissolve a lot of waste matters 
from the intestines. The pancreatic fluid acts on the fats, and 
continues the change of starch into sugar. As a total result, 
the elements of the food are reduced to a state fitting them for ab- 
sorption into the blood, and a large proportion of the soluble 
parts of the food are at once taken up by the small blood-vessels^ 
(capillaries) of the intestines. The fatty matters, with other 
portions of the food forming a white fluid like milk, are 
taken up by the special absorbents (lacteals), which carry them 
into the blood stream going towards the heart ; all that part of 
the food which is not dissolved and taken into the blood is 
carried into the large intestine, and expelled in the form of 
manure. 
Ruminants, as the ox and sheep, swallow their food after a 
little chewing ; and then, when the paunch is well filled, they 
rest, and re-chew the mass in small portions at a time, after 
which it passes through the other divisions of the stomach into 
the true digestive organ, where the same action takes place as 
goes on in the single stomach of the horse or pig. 
Urinary and Generative Organs. — It will not be possible for 
the farmer to get more than a general idea of the situation and 
form of the organs of the urinary and generative systems during 
the rough dissection of the carcass. 
When the stomach and intestines are taken out of the cavity 
of the abdomen, the kidneys, or at least the fat which covers 
them in fat animals, will be seen; and from the pelvic cavity 
formed by the hip-bones, the bladder, and in the female animal 
a portion of the womb (uterus), Avill protrude. Tiiese parts may" 
be examined by sawing away a portion of the hip-bone on one 
side, or they may be cut out and placed on a table. 
Fig. 30 shows at one view the urinary and generative organs 
of the male (horse). 
