276 PHYSIOLOGY. 



7. The stomach is the largest organ of digestion. It lies 

 immediately under the false ribs, on the left side, below the 

 midriff, and is shaped somewhat like a bag-pipe. It has two 

 openings, the upper one, which admits the food, is called car- 

 diac, and the lower one, the pyloric orifice. In a middle sized 

 man, this organ is about ten inches long, and three or four in 

 diameter, and holds from three to six pints. 



8. The stomach has four distinct coats ; the inner one is 

 called mucous or villous ; being thin, soft, and spongy ; the 

 second vascular ; as it is made up chiefly of blood vessels ; 

 the third muscular; composed of muscular fibres, and very 

 strong ; the fourth serous ; as it secretes a serous or watery 

 fluid. The stomach is freely supplied with blood vessels and 

 nerves; the latter being furnished partly from the spinal 

 marrow, and partly from the brain. 



Fig. 2. 



The human stomach : a, the esophagus or gullet ; &, the cardiac por- 

 tion ; c, the left extremity ; d, the small extremity ; e, the pylorus tied ; 

 g g, the omentum or caul, which is attached to the outside of the 

 stomach, and falls over the intestines like a curtain. 



