CHAPTER II. 



A GENERAL ACCOUNT OF THE LYMPHATIC SYSTEM. 



THE lymphatic system consists of the lacteals, the lymphatic 

 vessels, their common trunk the thoracic duct, and the glands 

 called conglobate. 



The lacteals begin from the intestinal tube, and can readily 

 be seen in a dog or other quadruped that is killed two or three 

 hours after eating, when they appear filled with a'white chyle. 

 The experiment succeeds best when the dog is fed with milk ; 

 but they do not always convey a white fluid, for, even in a 

 dog, if opened long after a meal, they are found distended 

 with a liquor that is transparent and colourless like the lymph ; 

 and in birds I have never found the chyle white, but always 

 transparent and limpid (see Note LIX) ; these vessels, therefore, 

 might with as much propriety be called the lymphatics of the 

 intestines. 



The lymphatic vessels are small pellucid tubes that have 

 now been discovered in most parts of the human body ; the 

 fluid they contain is generally as colourless as water, a circum- 

 stance which procured them at first the name of ductus aquosi, 1 

 and afterwards that of vasa lymphatica. 2 The course of the 

 lymph, like that of the chyle, is from the extreme parts of the 

 body towards the centre, and the lymphatic vessels commonly 

 lie close to the large blood-vessels. If, therefore, a ligature be 

 made round the large blood-vessels of the extremity of a living 

 animal, or of one just dead, that ligature, by embracing the 

 lymphatics, will stop the course of the lymph, which by dis- 

 tending the vessels will make them visible below the ligature. 



All the lacteals and most of the lymphatic vessels open into 

 the thoracic duct, which lies upon the spine and runs up towards 

 the neck of the animal, where it commonly opens into the 

 angle between the jugular and subclavian veins of the left 



1 See Rudbeck, 1. c. 2 See Bartholin, 1. c. 



