ALIMENTATION 



99 



which food is stored. Thus in feeding, vegetation is cropped by 

 the incisors of the lower jaw and swallowed unmasticated into the 

 rumen and reticulum. When the animal stops grazing, it seeks 

 a quiet spot and begins to chew its cud. In this process food 

 is regurgitated in small amounts from the reticulum to the 

 mouth and then thoroughly ground up by the premolar and 

 molar teeth. When the masticated food is swallowed, it passes 



DC 



SF 



Fig. 66. — Human alimentary tract, diagrammatic, ac, ascending colon; 

 bd, bile duct, extending from the liver to the duodenum; c, caecum; d, beginning 

 of duodenum; dc, descending colon; gb, gall bladder; l, liver, turned up so as to 

 show its under surface; o, end of esophagus; p, pancreas, whose duct connects 

 with the duodenum near the end of the bile duct; r, rectum; s, stomach; sf, sig- 

 moid flexure of descending colon; si, small intestine; tc, transverse colon; va, 

 vermiform appendix. 



into the psalterium and abomasum where it undergoes gastric 

 digestion (Fig. 65). 



The human stomach is sharply marked off from the esophagus 

 at the cardiac orifice and from the intestine at the pylorus (Fig. 

 66). Between the cardiac and pyloric regions it is enlarged 

 to form the fundus, which gives the stomach the shape of a 

 pouch with a greater and lesser curvature. The actual shape 

 of the human stomach varies considerably in different individuals 

 and in the same individual at different times. When empty, 



