NUTRITIVE FUNCTIONS DIGESTION. 277 



9. The intestines in man, are from five to six times the 

 length of the body ; and are divided into large and small in- 

 testines ; the latter making about four fifths of the whole. 

 The small intestines are divided into duodenum, jejunum, 

 and Ueon. The duodenum is so called because it is about 

 twelve finger's-breadth in length ; the jejunum from its gene- 

 rally being found empty ; the ducts or canals from the liver 

 and pancreas enter the duodenum near the middle, and it is 

 abundantly supplied with lacteals. The different portions 

 of the large intestine are called coecum, colon, and rectum. 



10. The liver is the largest gland in the body ; and it lies 

 directly under the ribs, on the right side, and reaching be- 

 low them. In a grown person, it is about ten inches in diam- 

 eter, and weighs not far from four pounds. It secretes the 

 bile, which is poured out into a bag called gall-bladder, con- 

 nected with it ; from thence it is carried into the duodenum. 

 The liver is found in all the vertebrated animals and in the 

 mollusca ; in birds, reptiles and fishes, its size is greater in 

 proportion to that of the body than in the human species. 

 It is attached to the diaphragm, which lies above it, by a 

 fold of the peritoneum, called the suspensory ligament of the 

 liver. 



11. The pancreas is a gland about five inches in length, 

 of a whitish colour, lying immediately behind the stomach. 

 It is supplied, like the stomach, with numerous blood-vessels 

 and nerves. It secretes a fluid, called the pancreatic fluid, 

 which is white, viscid, inodorous, slightly saline, and con- 

 tains a large proportion of albumen. This gland is found 

 in all the mammalia, in birds, and in amphibious animals, or 

 such as live both in air and water, like the frog ; but it is 

 much larger in animals that live on vegetables, than in those 

 that feed on flesh. Hence, the fluid which it secretes, is 

 supposed to aid in difficult digestion. (See Fig. 3.) 



24 



