182 



THE BLOOD AND ITS CIRCULATION. 



the most peripheral layers of the venous blood has been 

 accomplished : a bloody fluid is often extracted from the 

 vessels of a corpse, already in the state of cadaveric rigidity, 

 which, being placed in a vase in contact with the air soon 

 coagulates, almost like blood taken from a living animal. 



Coagulation in the corpse taking place thus slowly, we 

 have here all the conditions favorable to the separation of 

 the fibrine and the globules, and to the formation of a buffy- 

 coat (see buffy-coated blood, p. T26). The vessels, indeed, 

 may be considered as forming a reservoir of a complicated 

 form, in which during coagulation the fibrine and globules 

 are placed in layers according to their weight, the globules 

 in the inclined parts, the fibrine in those more raised, in the 

 form of colorless clots: whence the mixed clots, or those 

 formed partly of cruoric clots (centre and inclined parts of 

 the coagulated masses) and partly of discolored or buffy- 

 coated clots. In the latter, as in the buffy-coat formed 

 after coagulation in a vase, are found a large number of 

 white globules (Fig. 55), so many, sometimes, being joined 

 together, that they might easily be taken for a collection of 

 pus. 



Fig. 55. Fibrinous clSt without red globules.* 



The arrangement of these mixed clots is determined by 

 the position of the body after death: thus, the corpse being 

 generally laid upon the back, the clot in the vena cava is 

 colorless in the vicinity of the heart, and becomes darker 

 towards the lumbo-dorsal region, which is more inclined, 



* /, #, ;*, Thin fibrinous layer, showing the interlacing of the striae of the 

 iibrinous layer, i. k, Leucocytes united with the fibrine, and bleached by the 

 action of water (500 diain.) (Robin, " Traite" du Microscope.") 



