Chap. IV.] 



STOMACH OF MAMMALS. 



165 



In the heron, which lives especially on fish, which 

 it swallows whole, the stomach is of great size and 

 extent, reaching nearly to the anus, and occupying 

 the greater part of the abdominal cavity. 



In the Mammalia the stomach is often set more 

 or less at right angles to the longitudinal axis of the 

 body, and its upper is shorter than its lower curva- 

 ture, which may, 

 therefore, be distin- 

 guished from one 

 another as the 

 greater and the 

 less ; the enlarge- 

 ment of the cardiac 

 side of the stomach 

 is a little more 

 marked in the dog 

 and in man than in 

 the insectivorous 

 Gymnura, and very 

 much more so in the 

 rabbit. As the trans- 

 verse axis increases 

 in length, a division 

 into two parts be- 

 comes more or less well pronounced ; this is best seen 

 in the interior, and is very well marked in the case of 

 the horse (Fig. 74), where the white-coloured cardiac 

 portion, with its thick epithelium, is separated by a ridge 

 from the redder pyloric sac, with its softer epithelium 

 and its contained gastric glands. This separation of 

 the stomach into a reservoir and a digestive portion is 

 carried to an extreme in the ruminating Ungulates. 



In the peccary the stomach may be divided into 

 cardiac and pyloric regions, but the esophagus is 

 further remarkable for being continued on, in the 

 form of a groove, into the pyloric division ; in addition 



Fig. 74. Inner Face of the "Wall of the 

 Stomach of the Horse. 



a. Cardiac ; &, pyloric sac ; c, duodenal dilata- 

 tion. (After Chauveau.) 



