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 
