THE ALIMENTARY CANAL 291 



far as to make two or three sections. But animals 

 that chew the cud (ruminants) have the most complex 

 stomach. It is divided into four peculiar chambers : 

 First, the paunch (rumen), the largest of all, receives 

 the half-masticated food when it is first swallowed. 

 The inner surface is covered with papillae, except in 

 the camel, which has large cells for storing up water. 

 From this, the food passes into the honeycomb stomach 

 (reticulum), so named from its structure. Liquids swal- 

 lowed usually go directly to this cavity, without passing 

 through the paunch, and hence it is sometimes called 

 the water bag. Here the food is made into little balls, 



FIG. 254. Complex Stomach of a Ruminant: a, gullet; b, rumen, or paunch; c, reticu- 

 lum ; d, psalterium, or manyplies ; e, abomasus ; _/", pylorus leading to duodenum. 



and returned to the mouth to undergo a thorough mas- 

 tication. When finally swallowed, it is directed, by a 

 groove from the esophagus, to the third, and smallest, 

 cavity, the manyplies (psalterium), named from its 

 numerous folds, which form a strainer to keep back 

 any undivided food ; and thence it passes into the true 

 stomach (abomasus), from which, in the calf, the rennet is 

 procured for curdling milk in the manufacture of cheese. 

 This fourth cavity is like the human stomach in form 

 and function, and is the only part which secretes gastric 

 juice. The rumen and reticulum are rather dilatations 

 of the esophagus than parts of the stomach itself ; while 

 the latter is divided by constriction into two chambers, 

 the psalterium and abomasus, as in many other animals. 



