[ARACTERS OF LYMPH AND CHYLE. 211 



identical with the pale cells found in the blood ; (2), some red 

 blood corpuscles which give the fluid in the thoracic duct a 

 pinkish color; (3), a quantity of very finely divided fat, which 

 varies in proportion to the amount of fat recently digested ; (4), 

 other minute particles of unknown function and origin. 



When removed from the body and allowed to stand, the lymph 

 becomes converted into a soft jelly. This coagulation no doubt 

 depends upon chemical changes in the lymph which give rise to 

 fibrin. This subject will be discussed more fully in a future 

 chapter. The amount of fibrin formed in the lymph is very 

 small, and therefore the clot is very soft and shrinks considerably. 

 The quantity of chyle which can be obtained from the lacteals is 

 also small, and therefore the thorough investigation of it is diffi- 

 cult. The fluid from the tissues differs from the mixed lymph in 

 appearance and constitution only during digestion, and then 

 chiefly in containing a greater amount of fat and solids derived 

 from the intestinal cavity. The lymph of the thoracic duct con- 

 tains three forms of proteid : (1), serum albumin, which can be 

 coagulated by heat ; (2), alkali albumin precipitated by neutral- 

 ization ; and (3), globulin. It also contains in solution soap, 

 cholesterin, grape sugar, urea, leucin, and some salts, particu- 

 larly sodium chloride, and the sulphates and phosphates of the 

 alkalies. 



On their way to enter into the blood current both the lymph 

 and chyle undergo certain changes. Before passing through the 

 lymphatic glands the fluid contains much fewer lymph corpuscles 

 than after it has traversed the glands ; from this fact, and from 

 the structure of the lymph glands, we may conclude that they are 

 the chief sources of these white cells. The chyle of the lacteal 

 vessel of the mesentery contains particles of fat which greatly 

 exceed in size those found in the thoracic duct, so we may infer 

 that the fat emulsion undergoes a further subdivision or modifi- 

 cation on its way through the glands. 



The lymph which has been collected from the lymph channels 

 of the extremities has been found to contain less albumin than 

 that coming from the main trunk, and after long fasting the 

 lymph from the thoracic duct has the same characters. 



