352 CHYLE, LYMPH, TKANSUDATES AND EXUDATES. 



tion in the cells, bodies of high molecular weight are split into a number 

 of smaller molecules, which latter, either directly, if they leave the cells 

 and pass into the tissue-fluid, or indirectly, when they remain in the cells, 

 produce an increase in the osmotic tension within the cells, and in this 

 way cause a taking up of water from the fluid, and must therefore increase 

 the osmotic pressure of the tissue-fluids. As the cells can by synthesis 

 build up highly complex constituents from simple molecules, and as the 

 chief products of catabolism are carbon dioxide and water, it is difficult 

 to explain these intricate conditions. Still, irrespective of whatever 

 view, a change in one or the other direction in the osmotic pressure 

 upon both sides of the capillary wall must be produced thereby. Whether 

 this and other physico-chemical processes are alone sufficient to explain 

 the lymph formation (COHNSTEIN, ELLINGER) remains an open and 

 disputed question. 1 



H. TRANSUDATES AND EXUDATES. 



The serous membranes are normally kept moistened by liquids whose 

 quantity is sufficient only in a few instances, as in the pericardial cavity 

 and the subarachnoidal space, for a complete chemical analysis to be 

 made of them. Under diseased conditions an abundant transudation 

 may take place from the blood into the serous cavities, into the sub- 

 cutaneous tissues, or under the epidermis; and in this way pathological 

 transudates are formed. Such true transudates, which are similar to lymph, 

 are generally poor in form-elements and leucocytes, and yield only very 

 little or almost no fibrin, while the inflammatory transudates, the so-called 

 exudates, are generally rich in leucocytes and yield proportionally more 

 fibrin. As a rule, the richer a transudate is in leucocytes the closer it 

 stands to pus, while a diminished quantity of leucocytes renders it more 

 nearly like a real transudate or lymph. 



It is ordinarily accepted that filtration is cf the greatest importance 

 in the formation of transudates and exudates. The facts coincide with 

 this view that all these fluids contain the salts and extractive bodies 

 occurring in the blood-plasma in about the same quantity as the blood- 

 plasma, while the amount of proteins is habitually smaller. While the 

 different fluids belonging to this group have about the same quantities 

 of salts and extractive bodies, they differ from one another chiefly in 

 containing differing quantities of protein and form-elements, as well as 

 varying quantities of transformation and decomposition products of 

 these latter changed blood-coloring matters, cholesterin, etc. The 



^n this question see Ellinger, "Die Bildung der Lymphe," Ergebnisse der Phys- 

 iologic, I, Abt. 1, 355, and Asher, Biochem. Centralbl., 4, pp. 1 and 45. 



