36 BOARD OF AGRICULTURE. 



through which the trocar is passed in cases of hoven. The 

 second stomach ("reticulum," or honeycomb stomach as it 

 is called) has a very peculiar appearance in its interior, occa- 

 sioned by the unequal folding of its mucous membrane. It 

 is here that the singular provision of water-cells is found, 

 which in the camel has been developed to an unusual degree, 

 enabling it to go for many days without receiving a fresh 

 supply of water. This is developed more or less in all the 

 ruminants. The third stomach is called the " omasum," or 

 many plies, from the peculiar manner in which the lining- 

 membrane is disposed, which is much like the leaves of a 

 book. This is in order to bring the food in contact with a 

 large surface of the stomach. The fourth stomach is called 

 the " abomasum," or reed. This is the seat of the final and 

 true digestion, the gastric fluid being secreted from it alone. 

 It is the lining portion of this stomach in the calf that fur 

 nishes rennet, which, from its containing an organic acid, 

 possesses the power of coagulating milk, as illustrated iu 

 cheese-making. 



The next division is the intestinal canal, which is divided 

 into two portions, called the " small " and the " large intes- 

 tines." Anatomists again subdivide each of these, but the 

 present is enough for our purpose. The entire length of the 

 intestinal canal in the horse is about ninety feet, or about ten 

 times the length of his body ; the small intestine occupying 

 sixty-six feet, and the large twenty-four. That of the pig is 

 sixteen times the length of the body, in the proportion of 

 three to one as to large and small. The length in the ox is 

 twenty-two times that of the body, and in the sheep twenty- 

 seven times. 



The lacteals are very minute vessels, which commence in 

 the villi of the mucous surface of the small intestine, and pass 

 to a series of small glands called the "mesenteric glands," 

 and from these to more remote ones ; growing fewer but 

 larger every time, till they unite in a single one called the 

 "thoracic duct," which is in the human subject about the 

 size of a goose-quill, but grows smaller as its length increases, 

 which is about eighteen or twenty inches. It lies just over 

 the spinal column, and empties into the subclavian vein, one 

 of the large veins within the shoulder and near the neck. 



The accessory glands are the salivary glands of the mouth ; 



