SECTION XII 

 LYMPHATIC SYSTEM 



THE Lymphatic System is the means by which the liquid 

 portion of the blood which exudes into the intercellular spaces 

 is gathered up and returned to the blood, passing through the 

 lymphatic glands on its way. The lymph capillaries gather up 

 the fluid from the spaces, and enter a definite system of vessels, 

 which carry the lymph to the groups of glands. Vessels leave 

 these glands, and the lymph is carried to its final destination 

 in the big veins at the root of the neck by one of the two ter- 

 minal lymph vessels. 



The Thoracic Duct is the larger of the two terminal vessels. 

 It commences in the Receptaculum chyli (really a dilation of 

 the vessel) which lies beneath the right crus of the diaphragm. 

 The duct passes through the aortic opening in the diaphragm, 

 and passes up on the right of the vertebral column. At the level 

 of the fifth thoracic vertebra it crosses over to the left side, and 

 passes up to enter the left innominate vein. The Receptaculum 

 chyli receives the lymph from the lower extremities and the 

 whole of the abdomen. The thoracic duct receives lymph from 

 the left half of the thorax, the left upper extremity, and the left 

 side of the head and neck. 



The Right Lymphatic Duct is a very short vessel, not always 

 present, about an inch long, which enters the right innominate 

 vein. It receives lymph from the right half of the thorax, right 

 upper extremity, and the right side of the head and neck. 



The Lymphatic Glands and their vessels are arranged in two 

 sets superficial and deep and are usually to be found on the 

 course of the big veins and large spaces where there is con- 

 nective tissue. The two sets anastomose with one another freely. 



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