STRCCTURE AND OPPICE OF THE STOMACH. 13 



of it, like a portion of intestine, can be contracted separately; greater num- 

 and when its length, and the thinness of its coats are consi- " ^ "^ ' 

 dered, this action becomes necessary to propel the food from 

 one extremity to the other. Such u structure of stomach 

 makes regnrgitation of its contents into the mouth very ea- 

 sily performed. The food in this stomach goes through scr 

 veral preparatory processes ; it is macerated in the cuticular 

 portion; it has the secretion from the pouch at the cardia 

 mixed with it; and is occasionally ruminated. Thus pre- 

 pared, it is acted on by the secretion of the solvent glands, 

 which probably are those met with in clusters in the course 

 of the longitudinal bands, and afterward converted by the 

 secretions near the pylorus into chyle. 



The animals, whose stomachs have processes or pouches Animals with 

 at their cardiac extremity, are the kanguroo, hog, pecari, P™^^^^^*' ^^ 

 hippopotamus, and elephant. 



The pecari's stomach bears the nearest resemblance to Pecari. 

 those with cuticular reservoirs, having a portion of its surface 

 lined with cuticle; but it only extends to a small distance 

 from the termination of the oesophagus, and is not continued 

 ©ver any part of the great curvature. 



The hippopotamus's stomach I have never seen, and DaUf Hippopotamus 

 benton's description and engravings are taken from that of 

 a foetus; so that the structure of its mmute parts is imper- 

 fectly known ; but there is no doubt of there being a large 

 pouch on each side of the cardiac portion, and there is rea- 

 son to beheve, that no part of the cavity of the stomach is 

 lined with cuticle. 



The elephant's stomach is the most simple of this kind. Elephant. 

 It has no cuticular lining; the elongation at the cardia is 

 only a continuation of the general cavity, distinguished from 

 it by the membranous septa ; and the broad one may act as 

 a valve, and occasionally preclude the food from passing. 



In these stomachs the pouches at the cardia can only be 

 connected with the preparation of the food, softening it by 

 means of their secretions, or retaining it within their cavi- 

 ties; the other glandular structures are similar to those in the 

 ass and rat, only more conspicuous. 



It is deserving of remark, that the internal structure oflnphytivorou; 



the stomachs fitted for digesting vegetable substances, cor- *"'™»'* '*"'' 

 ° ° '^ structure of 



responds 



