THE ABSORBENT SYSTEM. 



95 



it is dissolved, and, therefore, there is a constant loss in 

 the passage down the canal. In the mouth and oesoph- 

 agus, the absorption is slight; but much of that which 

 has yielded to the gastric juice, with most of the water, is 

 greedily absorbed by the capillaries of the stomach, and 

 made to join the current of blood which is rushing to the 

 liver. Absorption by the capillaries also takes place from 

 the skin and lungs. Medicinal or poisonous gases and 

 liquids are readily introduced into the system by these 

 channels. 



We have seen that the oily part of the food passes un- 

 changed from the stomach into the small intestine, where, 

 acted upon by the pancreatic juice, it is cut up into ex- 

 tremely minute particles, and that the undigested albumi- 

 noids and starches are digest- 

 ed in the intestine. Two 

 kinds of absorbents are pres- 

 ent in the intestine, lacteals 

 and blood -capillaries. Both 

 the lymphatic and blood sys- 

 tems send vessels into the 

 velvety villi* 1 with which the 

 intestine is lined. The blood- 



mi • t . i ,i , Fig. 60.— Lacteal System of Mammal : a. 



Capillaries lie towards the OUt- descending aorta, or principal artery ; 



mdp of thp villus anrl Hip 6 ' thoracic duct < c > ori g il1 of lacteal 

 blue Or tlie VlliUS ana the vesse ls, ^, in the walls of the intestine, 



lacteal in the Centre. The d >' e ' mesentery, or membrane attach- 

 ing the intestine to walls of the body; 

 albuminoids and SUgarS are /, lacteal, or mesenteric, glands. 



chiefly absorbed by the blood-vessels and go to the liver. 

 The fats pass on into the lacteals, w T hich receive their 

 name from the milky appearance of the chyle. These 

 lacteals unite into larger trunks, which lie in the mesen- 

 tery (or membrane which suspends the intestine from the 

 back wall of the abdomen), and these pour their contents 

 into one large vessel, the thoracic duct, lying along the 

 backbone, and joining the jugular vein in the neck. 



