112 DIGESTION 



branch into capillaries in the submucous layer. The mus- 

 cular coat is made up of unstriped muscle fibers, and varies 

 greatly in thickness at different parts. It is thickest at 

 the pyloric end. The outermost layer of fibers is a con- 

 tinuation of the longitudinal fibers of the esophagus and is 



FiGr. 37 — Longitudinal section of tlie stomach ; a, esophagus ; 6, greater curvature ; 

 c, lesser curvature ; d, sphincter pylorus ; /j-i, small intestine, !Hie ridges in 

 the stomach are folds of mucous membrane. 



thickest over the curvatures of the stomach. The circular 

 muscle fibers of the esophagus are likewise continued, and 

 form the iimer layer of muscle over the stomach. This 

 circular layer becomes thickest at the pyloric end. Between 

 these two layers is a very incomplete oblique layer whose 

 fibers radiate from the cardiac orifice. The thick ring of 

 circular fibers at the pyloric end is called the sphincter > 

 -pylorus, and controls the entrance of food into the small 

 intestine. 



