THE LYMPH AND ITS MOVEMENT 



hand, and with certain blood vessels on the other, is a 

 system of tubes that return the lymph to the blood stream. 

 The smallest of these, and the ones in greatest abundance, 

 are called lymphatics. 

 They consist of slender, 

 thin-walled tubes, which re- 

 semble veins in structure, 

 and, like the veins, have 

 valves. They differ from 

 veins, however, in being 

 more uniform in size and 

 in having thinner walls. 



The lymphatics in differ- 

 ent places gradually con- 

 verge toward, and empty 

 into, the two main lymph 

 tubes of the body. The 

 smaller of these tubes, 

 called the right lymphatic 

 duct, receives the lymph 

 from the lymphatics in the 

 right arm, the right side of 

 the head, and the region 

 of the right shoulder. It 

 connects with, and empties 

 its contents into, the right 

 subclavian vein at the place 

 where it is joined by the FIG. 28. Diagram of drainage sys- 

 . , . . , . /T ^. ox tern for the lymph, i. Thoracic duct. 



right jugular vein (Fig. 28). 2 Right lymptfatic duct . 3 . Le f t sub - 



The larger of the lymph clavian vein. 4. Right subclavian vein. 



tubes is called the thoracic 5- Su P erior vena cava - 6 - Lacteals. 



. 7. Lymphatic glands. The small tubes 



duct. This receives lymph connec ting with the lymph spaces in all 

 from all parts of the body parts of the body are the lymphatics. 



