THORACIC DUCT. 



487 



Fig. 332. 



The general anatomy of the absorbents having been elsewhere detailed, 

 only their course and position remain to 

 be here described. They are gathered 

 into a right and a left trunk, which open 

 into the angles of union of the subclavian 

 and internal jugular veins. The large 

 vessel of the left side traversing the thorax 

 is named the thoracic duct : it receives not 

 only the lymphatics of its own side of 

 the head and arm, but likewise the lym- 

 phatics of both lower limbs, and the whole 

 of the lacteals. The vessel of the right 

 side is named the right lymphatic duct, and 

 receives lymphatics only. 



-5' 



Fig. 332. SKETCH OF THE THORACIC DUCT WITH 

 THE PRINCIPAL SYSTEMIC VEINS. 



The full description of this figure will be found 

 at p. 454. 



10, 10, indicate the thoracic duct ; the lower 

 number is close to the receptaculum chyli, the upper 

 is on the fourth dorsal vertebra, above which the 

 duct inclines to the left ; 6, on the left subclavian 

 vein, marks the termination of the duct in the 

 angle of uuion of the subclavian and internal jugu- 

 lar veins ; 5, on the right subclavian vein, indicates 

 the similar termination of the right lymphatic 

 trunk. 



1U 



THORACIC DUCT. 



The thoracic duct is the common trunk 

 which receives the absorbents from both 

 the lower limbs, from the abdominal viscera 

 (except part of the upper surface of the 

 liver), and from the walls of the abdomen, 

 from the left side of the thorax, left lung, 

 left side of the heart, and left upper limb, 

 and from the left side of the head and 

 neck. It is from fifteen to eighteen inches 

 long in the adult, and extends usually from 

 the second lumbar vertebra to the root of 

 the neck. Its commencement, however, is 

 often as low as the third lumbar vertebra ; 

 and in some cases as high as the first 

 lumbar, or even upon the last dorsal ver- 

 tebra. Here there is usually a dilatation 

 of the duct, of variable size, which is 

 called receptaculum chyli (Pecquet), and is 

 the common point of junction of the lym- 

 phatics from the lower limb with the trunks 

 of the lacteal vessels. 



The lower part of the thoracic duct is 

 generally wider than the rest, being about 

 three lines in diameter ; it lies at first to the right side of or behind the 



