THE STOMACH. 561 



layer is longitudinal; it is seen by raising the serous coat, 

 Is external, and extends from the oesophagus, with the 

 fibres of which it is continuous, and thence radiates to- 

 wards the pylorus, being found, in greatest abundance, 

 along the lesser curvature, though also seen upon the greater 

 curvature and extremity. The second, or middle layer, is 

 circular, commencing at the cardiac end, and increasing, in 

 the strength and number of its fibres, as it proceeds to the 

 pylorus. The fibres of the third or internal layer take u-e 

 oblique course, are most distinct on the great extremity, 

 and spread over the anterior and posterior surfaces of the 

 stomach. 



The third or proper coat of the stomach, is the internal, 

 mucous, or villous. This is connected to the muscular by 

 an intervening structure, termed nervous or fibrous, which 

 consists of fibres closely united, dense and strong, and re- 

 garded as the frame- F, G . 177. 

 work of the mucous 

 membrane, to which 

 it gives support, and 

 conducts its blood- 

 vessels and nerves. 

 The mucous mem- 

 brane is a continua- 

 tion of that lining the 

 oesophagus, and, ac- 

 cording to the obser- 

 vations of Dr. Beaumont, is constantly covered with a vis- 

 cid, transparent mucus. In its natural state it is of a 

 light or pale pink color, varying, however, with the full- 

 ness or emptiness of the stomach. It has a soft, velvet-like 

 appearance, whence its name the villous coat. 



When deprived of its mucus, by washing, and examined 

 with the microscope, in water, it presents a honeycomb 



FIG. 177 represents the Interior of the Stomach, a (Esophagus, b Cardiac 

 orifice of the stomach, c Its cul-de-sac, d Greater curvature, e Where 

 omentum majus is attached. / Muscular coat, g Cut edge of mucous coat. 

 k Rugae of mucous coat, t Lesser curvature, j Where duodenum begins, k 

 Pyloric orifice and valve. I Duodenum. 



36 



