216 DIGESTION. 



brane, especially in the superficial part of the corium, is a 

 quantity of a very delicate kind of connective tissue, called 

 retiform tissue (Fig. 72), or sometimes lymphoidor adenoid tis- 

 sue, because it so closely resembles that which forms the stroma, 

 or supporting framework of lymphatic glands (see section on 

 Lymphatic Glands); the resemblance being made much closer 

 by the fact that the interspaces of this retiform tissue are filled 

 with corpuscles not to be distinguished from lymph-corpuscles. 



At the deepest part of the mucous membrane, is a layer of 

 unstriped muscular fibres, called the muscularis mucosce, which 

 must not be confounded with the layers of muscle constituting 

 the proper muscular coat, and from which it is separated by 

 the submucous tissue. The muscularis mucosce is found in the 

 oesophagus, as well as in the stomach and intestines. 



When examined with a lens, the internal or free surface of 

 the stomach presents a peculiar honeycomb appearance, pro- 

 duced by shallow polygonal depressions or cells (Fig. 68), the 

 diameter of which varies generally from ^ O th to 3^ D th of an 

 inch ; but near the pylorus is as much as yj$th of an inch. 

 They are separated by slightly elevated ridges, which some- 

 times, especially in certain morbid states of the stomach, bear 

 minute, narrow, vascular processes, which look like villi, and 

 have given rise to the erroneous supposition that the stomach 

 has absorbing villi, like those of the small intestines. lu the 

 bottom of the cells minute openings are visible (Fig. 68), which 



FIG. 68. 



Small portion of the surface of the mucous membrane of the stomach (from 

 Ecker) 30_ The specimen shows the shallow depressions, in each of which the 

 smaller dark spots indicate the orifices of a variable number of the gastric tubular 

 glands. 



are the orifices of perpendicularly arranged tubular glands 

 (Fig. 69), imbedded side by side in sets or bundles, in the sub- 

 stance of the mucous membrane, and composing nearly the 

 whole structure. 



The glands which are found in the human stomach may be 

 divided into two classes, the tubular and lenticular. 



Tubular glands. The tubular glands may be described as a 

 collection of cylinders with blind extremities, about r^th of an 



