414 



ELEMENTAR Y ANA TOMY. 



[LESS. 



dilated into an enormous paunch, while close to the oeso- 

 phagus is a small chamber, called the reticulum (on account 

 of the net-like appearance of the free margins of the honey- 

 comb-shaped folds of its lining membrane). The rest of 

 the stomach is divided into a small chamber, the psalterium, 

 and a larger terminal portion, the abomasum. Two folds of 

 membrane lead from the lower end of the oesophagus to the 

 psalterium, and convey into it the food which descends after 

 that second mastication (called rumination} by which the 

 hastily swallowed grass, regurgitated from the paunch, under- 

 goes the requisite degree of comminution. 



Another complication of stomach is produced by an enor- 

 mous increase of the muscular coat of the pylorus. A 

 stomach so thickened is called a gizzard, and is found in 



FIG. 376. LONGITUDINAL SECTION OF THE STOMACH OF THE GREAT 

 ANT- EATER (Myrmecophaga jubata). 



ce, oesophagus ; c, cardiac division of the stomach ; in, thickened muscular walls 

 (or " gizzard ') of pyloric portion of stomach ; py, orifice of pyloric division ot 

 stomach. 



(After Owen.) 



most Birds, especially in those that feed on grain, as the 

 common Fowl. A gizzard may, however, be developed in 

 man's own class, as e.g. in the Great Ant-eater. 



Yet another form of complication is exemplified amongst 

 Mammals by the Dugong, which animal has two long caecal 

 appendages attached to its stomach. Many caecal appen- 

 dages may coexist, as in Fishes, but these open into the 



