130 THE PHYSIOLOGY OF DIGESTION AND ABSORPTION 



there is a more or less constant flow of lymph through these 

 spaces toward the lacteal. The tendency, therefore, of the 

 fats to enter the lacteal is physically natural. It is a curious 

 fact that the peptones and sugars, having penetrated the lin- 

 ing epithelium of the villus, enter the blood instead of the 

 lymph capillaries. 



A number of circumstances, such as the rate of absorp- 

 tion, the persistent direction of the current toward the blood 

 in the face of superior pressure, the disappearance of non- 

 osmotic substances from the canal, etc., are frequently at 

 variance with laboratory experiments. Application of 

 the laws of osmosis to the vital processes is seemingly sub- 

 ject to many variations, and explanation of many of the phe- 

 nomena of absorption in the body waits upon a clearer un- 

 derstanding of the so-called "vital activity" of the tissues. 



