80 APPLIED PHYSIOLOGY 



In front of the intestine, and partly enwrapping its folds, is a thin 

 apron of peritoneum, called the omentum. It contains much fat, and 

 acts as a cushion and as protection against cold. The small intestine 

 for about ten inches from the stomach is called the duodenum. Then 

 for about eight feet it is called the jejunum, and the remaining eleven 

 feet is called the ileum. There is no very marked difference between 

 any two sections of these divisions. 



The intestine ends at about the level of the hip bone, 

 and opens into the side of the large intestine by a slitlike 

 valve, which permits matter to pass into the large intes- 

 tine, but to a great extent prevents its backward movement. 



108. The large intestine, or colon. The whole large 



intestine is called the 

 colon. Its beginning 

 is a small pouch called 

 the ccecum, which is 

 situated on the right 

 side of the abdomen 

 at the level of the hip 



A piece of intestine showing the folds of the , 

 valvulae conniventes upon its inner surface. 



From the caecum 



there extends a small tube one quarter of an inch in 

 diameter and two inches long, closed at its outer end. 

 This tube is called the vermiform appendix. It sometimes 

 becomes inflamed, forming an abscess, and produces the 

 disease called appendicitis. 



The colon extends upward to the ribs, then crosses the 

 abdomen to the left side, and then extends downward. 

 These parts are called the ascending, transverse^ and de- 

 scending colon. The colon is held in place by a narrow 

 fold of peritoneum. It is not an even tube, but looks as 

 though strings were tied about it at intervals of a few inches. 



109. Structure of the intestine. The whole intestine 

 consists of a tube of muscular tissue, whose walls are 



