DIGESTION 



197 



Yet, with all these functions regularly performed by the normal stomach 

 people live stomachless with a tolerable degree of comfort. 



FIG. 94 



Longitudinal section of the pyloric region: P, the pylorus; D, duodenum; C.P., pyloric 

 canal; V.P., pyloric vestibule. (E. Mtiller.) 



The Small Intestine. The small intestine is a tube about 650 cm. long 

 and somewhat larger at the upper end than at the lower. It has practically 

 the same coats as the stomach. Exner and Bienenfeld suppose that the 

 so-called muscularis mucosse has for its function to prevent the puncture 



FIG. 95 



The two lymph-plexuses in the wall of the dog's stomach between which the muscularis 

 mucosae lies. 34 /i- (Mall.) 



of the gut by bones and other sharp objects. The mucous membrane is 

 made up of various secreting glands, of lymph-nodules, and of the villi 

 which extend inward from it. One set of glands called the duodenal 

 (or Briinner's glands) appear to the eye to be almost identical with those 



