412 HANDBOOK OF PHYSIOLOGY. 



The Lymphatic System. 



Having now discussed the methods and conditions of absorption in 

 general, we must next turn to the system of vessels in which, on the 

 one hand, materials of the food not taken directly into the hlood- vessels 

 of the alimentary canal are received and carried into the blood-stream; 

 and, on the other, fluid which has exuded from the blood-vessels into the 



Lymphatics of head and PBHH^H^IKJHIBSS Lymphatics of head and 

 neck, right. SSStfrilEl KlWH neck ' lef t - 



Right internal jugular vein, j K^S^OBIKfSof J^^^ Thoracic duct. 



Right subclavian vein, j gaga^KflHgJlKBima Left subclavian vein. 



Lymphatics of right arm. 



Thoracic duct. 



Receptaculum chyli. 



Lacteals. 



Lymphatics of lower extrem- ^BHlKi[fiBBQraMIpIB I Lymphatics of lower ex- 

 ities. BBS^tflloS^^^^B tremities. 



<nMuBvflVPvvS V*^W^BB^fir4**vr.lT.wmJBBH0 



Fig. 276. Diagram of the principal groups of Lymphatic vessels (from Quain). 



tissues is gathered up and carried back again into the blood. This sys- 

 tem of vessels is called the Lymphatic System, and the vessels themselves 

 are named Lymphatics or Absorbents. They have often been incidentally 

 mentioned in former (Chapters. 



The principal vessels of the lymphatic system are, in structure and 

 general appearance, like very small and thin-walled veins. They are 

 provided with valves. They commence in fine microscopic lymph-cap- 

 illaries, in the organs and tissues of the body, and they end directly or 

 indirectly in two trunks which open into the large veins near the heart 



