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HANDBOOK OF PHYSIOLOGY. 



have given rise to the erroneous supposition that the stomach has 

 absorbing villi, like those of the small intestines. In the bottom of 

 these little pits, and to some extent between them, minute openings are 

 visible, which are the orifices of the ducts of perpendicularly arranged 

 tubular glands (fig. 249), imbedded side by side in sets or bundles, on 

 the surface of the mucous membrane, and composing nearly the whole 

 structure. 



The glands of the mucous membrane are of two varieties, (a) Cardiac, 

 (b) Pylori c. 



(a) Cardiac glands are found throughout the whole of the cardiac 



en d of the stomach. They are arranged 

 in groups of four or five, which are sep- 

 arated by a fine connective tissue. Two 

 7 SJ M7^ or three tubes often open into one duct, 



Fig. 251. Fig. 252. 



Fig. 251. Section showing the pyloric glands, s, free surface: d, ducts of pyloric glands; n, 

 neck of same; m, the gland alveoli; mm, muscularis mucosae. (Klein and Noble Smith.) 



Fig. 252. Plan of the blood-vessels of the stomach, as they would be seen in a vertical section. 

 a, arteries, passing up from the vessels of submucous coat; 6, capillaries branching between and 

 around the tubes; c, superficial plexus of capillaries occupying the ridges of the mucous membrane; 

 d, vein formed by the union of veins which, having collected the blood of the superficial capillary 

 plexus, are seen passing down between the tubes. (Brinton.) 



which forms about a third of the whole length of the tube and opens on 

 the surface. The ducts are lined with columnar epithelium. Of the 

 gland tube proper, i.e., the part of the gland below the duct, the upper 

 third is the neclc and the rest the body. The neck is narrower than the 

 body, and is lined with granular cubical cells which are continuous with 

 the columnar cells of the duct. Between these cells and the membrana 

 propria of the tubes, are large oval or spherical cells, opaque or granular 

 in appearance, with clear oval nuclei, bulging out the membrana pro- 

 pria; these cells are called oxyntic or parietal cells. They do not form 

 a continuous layer. The body, which is broader than the neck and ter- 



