A STUDY OF BLOOD MANUFACTURE 115 



called the crop. Here the food is softened somewhat, and then 

 it is passed on into the stomach. This organ consists of & pro- 

 ven-trie' u-lus (Latin pro = before + ventriculus = little stom- 

 ach), the walls of which contain a large number of gastric 

 glands, and a thick-walled, muscular gizzard, which has a horny 

 lining. In the gizzard the food is ground, and this process 

 is assisted by the small stones that the bird swallows. The 

 intestine leaves the gizzard close to the opening from the 

 pro ventriculus, and forms a loop inclosing the pancreas. 

 The rest of the intestine is coiled in a more or less spiral 

 fashion. A gall bladder is absent; the bile ducts for this 

 reason pass directly from the right and left lobes of the 

 liver into the intestine. 



The Alimentary Canal of the Sheep. The majority of mam- 

 mals have as a . 

 stomach a simple 

 sac. But in some 

 of the hoofed 

 animals (cattle, 

 sheep, goats, deer), 

 this organ reaches 

 a high degree of 

 complexity. The F IG . 41. Stomach of an Ox (opened to show 

 grass eaten by Chambers). 



these animals is a = esophagus, d = psalterium. 



i .,T -,. 6 = rumen. e = abomasum. 



mixed with saliva c = reticulum . /= small intestine . 



and swallowed 



without mastication into a large sac called the ru'men. It is 

 either stored here or is passed on to a second sac, called from 

 its honeycombed wall the re-tic'u-lum. When the sheep or 

 cow has finished eating, the food in rounded masses is 

 forced back in lumps through the esophagus into the mouth 

 cavity, and is then thoroughly masticated. To this process 

 is given the name cud-chewing or ruminating. The pasty 

 mass is now swallowed a second time, passing almost imme- 

 diately into a third compartment of the stomach, the psal- 



