CHAPTER VII. 



CHYLE, LYMPH, TRANSUDATES AND EXUDATES. 

 I. CHYLE AND LYMPH. 



THE lymph is at least in part the mediator in the exchange of con- 

 stituents between the blood and the tissues. The bodies necessary for 

 the nutrition of the tissues pass from the blood into the lymph, and the 

 tissues deliver water, salts, and products of metabolism to the lymph. 

 The lymph, therefore, originates partly from the blood and partly from 

 the tissues. From a purely theoretical standpoint one can, according 

 to HEIDENHAIN, differentiate between blood -lymph and tissue-lymph 

 according to origin. It is impossible at the present time to completely 

 separate that which comes from the one or the other source. 



Chemically the lymph is the same as plasma and contains, at least 

 to a great extent, the same bodies. The observation of ASHER and BAR- 

 BERA, 1 that the lymph contains poisonous metabolic products, does 

 not contradict such an assumption, as no doubt these products are trans- 

 ferred to the blood with the lymph. Although the blood does not show 

 the same poisonous action as the lymph, still this can be explained by the 

 great dilution these bodies undergo in the blood, and the difference 

 between blood-plasma and lymph is 110 doubt of a quantitative nature. 

 This difference consists chiefly in that the lymph is poorer in proteins. 

 No essential chemical difference has been found between the lymph and 

 the chyle of starving animals. After fatty food the chyle differs from 

 the lymph in its wealth of minutely divided fat-globules, which gives it 

 a milky appearance; hence the old name "lacteal fluid." 



Chyle and lymph, like the plasma, contain seralbumin, serglobulins, 

 fibrinogen, and fibrin ferment. The two last-mentioned bodies occur only 

 in very small amounts; therefore the chyle and lymph coagulate slowly 

 (but spontaneously) and yield but little fibrin. Like other liquids poor 

 in fibrin ferment, chyle and lymph do not at once coagulate completely, 

 but repeated coagulations take place. 



The extractive bodies seem to be the same as in plasma. Sugar (or 

 at least a reducing substance) is found in about the same quantity as in 



1 Zeitschr. f. Biologie, 36. 



327 



