THE LIVER. 323 



from its closed upper end, and the caecum, CC, is that part 

 of the large intestine Avhich extends beyond the communi- 

 cation. From it projects the vermiform appendix, a narrow 

 tube not thicker than a cedar pencil, and about 10 centi- 

 meters (4 inches) long. The colon commences on the right 

 side of the abdominal 1 cavity where the small intestine com- 

 municates with the large, runs up for some way on that 

 side (ascending colon, AC), then crosses the middle line 

 (transverse colon, TO) below the stomach, and turns down 

 (descending colon, DC] on the left side and there makes an 

 S-shaped bend known as the s ] igmoid flexure, 8F; from this 

 the rectum, R, the terminal straight portion of the intes- 

 tine, proceeds to the anal opening, by which the alimentary 

 canal communicates with the exterior. In structure the 

 large intestine presents the same coats as the small. The 

 external stratum of the muscular coat is not, however, 

 developed uniformly around it, except on the rectum, but 

 occurs in three bands separated by intervals in which it is 

 wanting. These bands being shorter than the rest of the 

 tube cause it to be puckered, or sacculated, between them. 

 The mucous coat possesses no villi or valvulae conniventes, 

 out is usually thrown into effaceable folds, like those of 

 the stomach but smaller. It contains numerous closely set 

 glands much like the crypts of Lieberkiihn of the small 

 intestine. 



The Ileo-Colic Valve. Where the small intestine joins 

 the large there is a valve, formed by two flaps of the mucous 

 membrane sloping down into the colon, and so disposed as 

 to allow matters to pass readily from the ileum into the 

 large intestine but not the other way. 



The Liver. Besides the secretions formed by the glands 

 imbedded in its walls, the small intestine receives those of 

 two large glands, the liver and the pancreas, which lie in 

 the abdominal cavity. The ducts of both open by a com- 

 mon aperture into the duodenum about 10 centimeters 

 (4 inches) from the pylorus. 



The liver is the largest gland in the Body, weighing from 

 1400 to 1700 grams (50 to 64 ounces). It is situated in the 

 upper part cf the abdominal cavity (le, le,' , Fig. 1), rather 

 more on the right than on the left side and immediately below 



