THE BLOOD AND LYMPH. 135 



fibrin-forming elements may be liberated from the bodies of leuco- 

 cytes that find lodgement behind the obstruction and suffer injury, 

 or they may be derived from blood-plates that have been arrested 

 and undergone similar changes. In a like manner, fibrin may be 

 formed in the lymphatic vessels or the interstices of the tissues. 1 



1 An explanation of fibrin-formation, offered by Lilienfeld, would serve to 

 elucidate many cases of coagulation under morbid circumstances. According to 

 this observer, fibrin is formed by the union of "thrombosin" with calcium, and is, 

 therefore, a calcium-thrombosin compound. The thrombosin is produced from 

 fibrinogen by the action of nuclein, which in turn is formed from the nucleohiston 

 contained in the nuclei of cells. Coagulation, then, would be the result of the 

 following process : the nucleohiston in the nuclei, during " karyolysis " or disintegra- 

 tion of the nucleus, is decomposed into "histon" and nuclein. The latter, acting 

 on fibrinogen, produces thrombosin, which unites with calcium to produce fibrin. 



