86 



THE PHYSIOLOGY OF DIGESTION AND ABSORPTION 



lined by cuboidal epithelium which discharges its secretion 

 into the lumen, this lumen being only a continuation of the 

 duct. These cuboidal cells are called peptic cells because 



FIG. 37. Vertical section of the gastric mucous membrane. 



S, g, pits on the surface; p, neck of a fundus-gland opening into a duct, g; x, 

 parietal, and y, chief cells; a, v, c, artery, vein, capillaries; d, d, lymphatics, 

 emptying into a large trunk, e. (Landois.) 



they produce pepsin, or its forerunner, pepsinogen. The 

 fundic (acid) glands are found to have lying close to the 

 basement membrane a number of large cells at intervals be- 



