THE STOMACH. 



1621 



Structure. The walls of the stomach, thickest and most resistant near the 

 pylorus, consist of four coats, the mucous, the submucous or areolar, the muscu- 

 lar, and the serous. 



The mucous coat or mucosa is soft and velvety, easily movable on the lax 

 subjacent areolar tissue, thickest near the pylorus, and presents many folds or ruga, 

 which during distention are more or less completely effaced. The folds are in the 



FIG. 1371. 



Falciform ligament 



Duodenum 

 Gall-bladder. 



Ascending colon 



Left lobe of liver 



Transverse mesocolon 



Transverse colon 



Jejunum 



Descending colon 



Ileum 



r Sigmoid 



Abdominal organs of formalin subject ; stomach has been removed to show that part of its " bed " formed by trans- 

 verse mesocolon and colon. 



main longitudinal, especially at the pyloric end, but many smaller ones run in all 

 directions. 



The epithelium covering the free surface of the mucous membrane consists of a 

 simple layer of tall columnar elements, from .020-. 030 mm. in height, many of which 

 are goblet-cells engaged in producing the mucus lubricating the gastric surface. At 

 the passage of the oesophagus into the stomach, some 23 cm. below the diaphragm, 

 the opaque stratified squamous epithelium of the gullet abruptly changes into the 



