ELEMENTARY PHYSIOLOGY 



The lymphatic capillaries in other parts of the body have 

 their origin in the spaces between the various structures. Their 

 office is to collect the fluid part of the blood which exudes through 

 the walls of the blood-vessels, and substances which, though 

 having once formed part of a tissue, are not yet waste materials, 

 but are capable of reorganisation, and may therefore be adapted 

 for nutrition. 



The lymph thus absorbed by the lymphatic capillaries is col- 

 lected by the lymphatic vessels, and transmitted through lymphatic 

 glands^ becoming more and more like blood (excepting in colour) 

 as it proceeds. 



All the lymphatic vessels, including those which convey the 

 chyle from the intestines, finally empty their contents into one of 

 the two lymphatic ducts. The smaller of these, called the right 

 lymphatic duct, enters a large vein at the right side of the root of 

 the neck. The larger duct the thoracic duct lies just in front 

 of the vertebral column. Its lower end, situated in the upper 

 portion of the abdomen, is four or five times as wide as the upper 

 part, and is called the receptaculum chyli or receptacle of the 

 chyle. The remainder of the duct lies at the back of the thorax, and 

 its upper end leads into a larger vein at the root of the neck on the 

 left side. Thus we have been able to trace the passage of food 

 materials from the mouth, till they finally enter the blood system. 



Absorption by Blood- 

 vessels 



LYMPHATIC 

 SYSTEM 



r Lacteals 



Other 

 Lymphatics 



Glands 



Thoracic duct 



SUMMARY. 



iFrom the mucous membrane in all parts of the 

 alimentary canal. 

 No power of selection 

 Every kind of food absorbed if dissolved, or if so 

 finely divided that it can permeate the walls of 

 the blood capillaries. 



The lymphatics of the intestines. 



Many originate in the villi of the small 

 intestine. 



/ During digestion a milky fluid 



Contain j (chyle"]. 



* During fasting a watery fluid. 



Absorb fatty substances. 



Absorb the fluid portion of blood (lymph) 



which has exuded through the blood-vessels. 



Also other substances for reorganisation. 



Engaged in elaborating blood from the 

 lymph and chyle. 



In front of backbone, chiefly in thorax. 



Receptaculum chyli lower portion situ- 

 ated in the abdomen. 



Receives lymph and chyle, and pours them 

 into the blood system. 



