STOMACH. 



301 



STOMACH. 



The stomach is a dilatation of the alimentary canal, continuous 

 ■with the oesophagus and small intestine, where the food is con- 

 verted into chyme, by maceration and the action of the gastric 

 juice. In the horse it is small in proportion to the size of the 

 animal, and rests in the left hypochondriac region, stretching when 

 full into the epigastric ; when distended, it resembles a bent tube 

 with two lateral dilatations, divided by a central constriction into 

 a left, or cardiac, and a right, or pyloric portion. The former is 



Fio. 98. 

 Posterior view of the stomach of a Horse, a, Left eul-de-nac; b. Right 

 eul-de-sac; e. Greater curvature ; d. Lesser curvature ; e, (Esophagus; 

 /, Duodenum. 



the larger, and called the greater cul-de-sac, or fundus; the right 

 portion, is the lesser cul-de-sac, or antrum pylori. It has one 

 opening on the left, leading into the oesophagus, through which 

 the food enters ; this is the cardiac orifice ; and another on the 

 right, which communicates with the first portion of the intestine 

 called the duodenum ; this is the pyloric orifice. At the pyloric 

 orifice there is a constriction called the pyloric ring. Between 

 the two openings the upper and lower borders are termed the 

 •curvatures, the superior or lesser being concave, the inferior or 

 greater convex. 



The curvatures indicate the division of the surface of the 

 stomach into two portions, an anterior and posterior. The 



