DIGESTION 



183 



Rontgen rays, have we come to possess actual knowledge on this matter. 

 The shape of the stomach depicted in the anatomies, an organ with an 

 unbroken greater curvature extending from the pylorus to the left around 

 the fundus and up to the cardia, exists only immediately after a large 

 meal, when the viscus is distended with food and drink. One sees it so, 

 in other words, only before the proper action and contraction of the organ 

 has begun to make headway over the contained mass. Far from being 

 a simple bag closable at its lower end by the pyloric valve, the stomach is 

 essentially a double organ in the same sense that the stomach of the sheep 

 has several chambers, although the omnivorous nature of man does not 

 necessitate the elaborate mechanism needed for rumination. The human 



FIG. 85 



The stomach of a ruminant (sheep) partly laid open: a, esophagus; g, reticulum; h, channe 

 for swallowed food; i, omasum, or psalterium; I, abomasum (rennet, or chemical stomach); c, b, 

 rumen (reservoir-stomach). (Caru.s and Otto.) 



stomach is divided into parts, the fundus or left-hand distended portion, 

 and the antrum, the active organ of digestion proper. This division is 

 more obvious functionally than appears in the structure of the post- 

 mortem organ. The parts are equal y important, for, as we shall see, 

 the mechanical functions of the stomach are at least as important as its 

 uses in the way of chemical digestion. 



The fundus, formerly called the cardiac end of the stomach, has move- 

 ments which are gentle and slow compared with those of the antrum and 

 of the small intestine. The fundus is largely a reservoir, and its motions 

 correspond to such a use. They are of a gentle and slowly peristaltic 

 nature just powerful enough to keep the antrum supplied with material 

 for its solution into chyme. It appears from work by Austin and by 



