STRUCTURE OF THE STOMACH. 267 



shared with the mucous membrane of the small and large 

 intestines, which, doubtless, are connected with the peculiar 

 functions, especially those relating to absorption, which 

 these parts of the alimentary canal perform. 



Entering largely into the construction of the mucous mem- 

 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 lymphoid or adenoid 

 tissue, because it so closely resembles that which forms the 

 stronia, 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 distin- 

 guished from lymph-corpuscles. 



At the deepest part of the mucous membrane, is a 

 layer of unstriped muscular fibres, called the muscularis. 

 mucosfc, 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 mus- 

 cularis mucoscB 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, 

 produced by shallow polygonal depressions or cells (fig. 68), 

 the diameter of which varies generally from --^-th to 

 ^4-^th of an inch ; but near the pylorus is as much as J-o-th 

 of an inch. They are separated by slightly elevated ridges^ 

 which sometimes, especially in certain morbid states of the 

 stomach, bear minute, narrow, vascular processes, which 

 look like villi, and have given rise to the erroneous suppo- 

 sition that the stomach has absorbing villi, like those of 

 the small intestines. In the bottom of the cells minute 

 openings are visible (fig. 68), which are the orifices of per- 

 pendicularly arranged tubular glands (fig. 69) imbedded side 

 by side in sets or bundles, in the substance of the mucous 

 membrane, and composing nearly the whole structure. 



