DIGESTION. 



FIG. 36. 



lar debris, which is at last dis- 

 solved. The fat also progres- 

 sively disappears, and the vesicles 

 may be seen in the lower part of 

 the intestine completely collapsed 

 and empty. 



,. , ,. . , FROM LAST QUARTER OF SMALL INTESTINE. a, 



In this Way the digestion OI the a . F at vesicles, quite empty and shrivelled. 



food goes on continuously through- 

 out the small intestine. At the same time it results in the production of 

 three different substances, namely : 1st. Peptone, from the digestion of 

 albuminous matters; 2d. Chyle, from the emulsion of the fats; and 3d. 

 Glucose, produced by the transformation of starch. These substances 

 are then ready to be taken into the circulation ; and as the mingled in- 

 testinal contents pass successively downward, the products of digestion, 

 together with the digestive secretions, are absorbed by the mucous mem- 

 brane and carried away by the blood-vessels. 



The Large Intestine and its Contents. 



The mucous membrane of the large intestine is provided with tubular 

 follicles not essentially diiferent in their anatomical characters from the 

 follicles of Lieberku'hn. Their secretion, however, appears to be scanty. 

 According to Ranke, fistulous openings in the large intestine do not yield 

 any notable quantity of fluid, and if a loop of the gut be isolated by liga- 

 tures, an accumulation of mucus-like matter is the only result. In the 

 rabbit, after ligature of the vermiform appendix, Funke obtained, at the 

 end of from two to four hours, a quantity of turbid alkaline secretion 

 with which the appendix had become filled. This fluid was without 

 action on coagulated albumen ; but it transformed starch into sugar, and 

 also decomposed the sugar with production of lactic and butyric acids. 

 The same change was produced on starch introduced into the cavity 

 of the appendix.* This accounts for the acid reaction sometimes found 



* Ranke, Physiologic des Menschen. 



N 



Leipzig, 1872, p. '297. 



