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ANATOMY AND PHYSIOLOGY 



Within the tissues of the body the lymph vessels are too small 

 to be seen by the naked eye, but they unite again and again to 

 form larger ones (although still very small) which in some places 

 may be seen entering or leaving glands, until finally two remain 

 the right lymphatic duct and the thoracic duct, which have a diameter 

 of 3 or 4 mm. 



FIG. 150. LYMPHATIC VESSELS AND NODES. 

 i and 2 are portions of the THORACIC DUCT. (Sappey.} 



Lymph is a transparent watery saline fluid with lymph cor- 

 puscles floating therein. It contains nutritive substances for the 

 tissues and waste matters derived from them. 



The description of plasma applies very well to lymph, always keeping in 

 mind that lymph is more watery and carries lymph cells while plasma bears 

 blood cells; lymph coagulates but slowly and not so firmly, with a pale clot 

 because of the absence of red cells. 



The origin of lymph is primarily from the blood. The walls of 

 the blood-capillaries allow a transudation of thin plasma or serum 



