The Digestive System 175 



different regions, the pyloric region, as seen under 

 low magnification, will now be described (Fig. 



45). 



The mucosa, m, consists of fairly long glands 

 underlaid by a well-marked muscularis mucosa, mm, 

 the latter exhibiting a compact circular layer over 

 a wider but more scattered layer of longitudinal 

 fibers. A considerable amount of fibrous con- 

 nective tissue lies among the muscle fibers. The 

 circular layer of the muscularis mucosa sends 

 towards the surface numerous strands or septa 

 between the glands ; six or eight of these are seen in 

 the figure. These strands are not nearly so nu- 

 merous in the large region of the stomach. As 

 was said, the outer or longitudinal layer of the 

 muscularis mucosa is wider but less compact than 

 the circular and its bundles of fibers are seen in the 

 figure as a layer of large, scattered, dots just beneath 

 the circular layer. 



The submucosa, sm, is of average thickness and 

 density. In the fundic and cardiac regions it 

 seems to extend between the circular and oblique 

 layers; at any rate, there is a considerable layer 

 of connective tissue between these two muscular 

 layers. 



The circular muscular layer, cm, is of only moder- 

 ate thickness and is of rather a loose character. 

 In the pyloric region it is not very distinct from 

 the underlying oblique layer, but in the other 

 regions, as has just been said, it is separated from 



