ABSORPTION FROM THE ALIMENTARY CANAL 1 27 



tion and passage thence to the left subclavian vein. Those 

 lymph capillaries which are concerned in this absorption oc- 

 cupy the villi, and are called lacteals. 



(A) From the Stomach. Since all classes of food except 

 fats have been partly digested in the stomach, it follows that 

 all except fats may be absorbed here. However, as a mat- 

 ter of observation, the stomach is of much less importance 

 in absorption than was once thought. Practically, it is found 

 that water and salts are passed quickly on toward the duo- 

 denum and are not largely absorbed in the stomach. Sugar 

 and peptones are also found to be absorbed rather sparingly 

 here. All these substances can undoubtedly be absorbed by 

 the gastric mucous membrane, and their complete absorption 

 is prevented only by their removal through the pylorus. It 

 is interesting to note that alcohol and condiments, like pep- 

 per and mustard, greatly hasten absorption, either by in- 

 creasing the blood flow or by directly stimulating the "vital 

 activity" of the epithelium. 



(B) From the 'Small Intestine. Here absorption of all 

 classes of food is possible, and here in fact most of the foods 

 are absorbed. The digestive influences are more active upon 

 all the aliments, the mucous membrane is well adapted to 

 absorption by reason of its valvulae conniventes and its villi, 

 and the food necessarily remains in the small intestine for a 

 considerable time. The fats are absorbed in the upper 

 part of the small intestine ; for they pass into the lacteals of 

 the villi, and these do not exist in the lower ileum. The 

 fluids swallowed are almost completely absorbed here, but 

 their place is taken by the intestinal secretions. The pro- 

 teids are absorbed to the extent of 85 per cent., more or 

 less, before reaching the large intestine, and the carbohy- 

 drates almost entirely disappear. 



(C) From the Large Intestine. The absorption process 

 in the large intestine is quite active. The passage of the 

 mass through it is slower, and even occupies an absolutely 

 greater time than the journey through the much longer small 



