PYLORIC GLANDS OF THE STOMACH. 



323 



where the mucous membrane is more yellowish-white in colour 

 (Fig. 135, A). These glands are generally branched at their lower 

 ends, so that several tubes open into a single duct [which, in contra- 

 distinction to the duct of the other glands, is wide and long, extending 

 often to half the depth of 

 the mucous membrane. 

 The duct is lined by epi- 

 thelium like that lining 

 the stomach, while the 

 secretory part is lined by 

 a single layer of short, 

 finely granular, columnar 

 cells, whose secretion is 

 quite different from that 

 of the cells lining the duct. 

 The lumen is well-defined. 

 Nussbaum has occasionally 

 found other cells, which 

 stain deeply with osmic 

 acid, between the bases 

 of these. Ebstein regards 

 these cells as forming 

 pepsin. It is to be remem- 

 bered that the appearance 

 of the cells differs ac- 

 cording to their state of 

 physiological activity 

 (Figs. 137 and 138). When 

 they are exhausted they 

 are smaller and more gran- 

 ular, owing to the denser 

 reticulation of their net-work ; at any rate, they are granular in pre- 

 parations hardened in alcohol (Fig. 138).] 



Muscularis MUCOSSB. The glands are supported by very delicate connective- 

 tissue mixed with adenoid-tissue (Fig. 134). Below this are two layers, circular 

 and longitudinal, of non-striped muscle, the muscularis mucosce, and from it fine 

 processes of smooth muscular fibres pass up between groups of the glands towards 

 the free epithelial surface of the gastric mucous membrane. These muscular 

 processes are said to be concerned in emptying the glands. [In the gastric mucous 

 membrane of the cat, there is a clear homogeneous layer which is stained red by 

 picrocarmine, and placed immediately internal to the muscularis mucosge. It is 

 pierced by the processes passing from the muscularis mucosse.] 



Masses of adenoid-tissue occur in the mucous membrane, especially near the 

 pylorus, constituting lymph-follicles, which are comparable to the solitary glands 

 of the small intestine. 



Fig. 135. 



A, Isolated pyloric gland ; d, isolated goblet 

 cells. 



