192 HUMAN PHYSIOLOGY 



differentiated that two regions suggest at least remotely 

 the two contrasted organs of the bird. Food is re- 

 ceived at first into the main or fundic part of the stomach 

 which is a pouch with rather thin walls. It has for a 

 prominent function the immediate bestowal of a meal. 

 An allied service is to transmit food slowly to the nar- 

 rower, right-hand part of the stomach leading to the 

 pylorus. This is the region called the antrum. 



.XL. 



FIG. 42. Above, the stomach is shown in a distended but inactive 

 state. Below, it is creased by peristaltic waves which thrust toward the 

 pylorus. 



The dotted line (d-d) suggests the surface of the diaphragm, (I) is in 

 the space occupied by the liver, (sp) near the position of the spleen. 

 The lesser omentum and the transverse colon are suggested in the upper 

 figure. 



The fundus relaxes in an accommodating manner when 

 one is eating. When the meal is secure, it exerts a 

 steady pressure upon it without agitating it to any extent. 

 This sustained pressure insures that, when any of the 

 contents passes to the intestine, more will promptly slip 

 into the antrum. Two hours after a meal the fundus 



