150 MANUAL OF PHYSIOLOGY. 



after all, this is a mere difference in degree, for how can we dis- 

 tinguish between the failure of a tissue to re-integrate or repair 

 its normal chemical changes upon which its life depends, and the 

 inevitable result of this failure (if prolonged beyond a certain 

 point) namely, its death ? 



When white cells congregate at a point from which the intima 

 is stripped from a vessel; their more active exertion possibly pro- 

 duces more ferment, etc., and at the same time they remain at the 

 injured part of the vessel wall, and the removal of Uae fibrin factors 

 cannot occur, since the intima is destroyed ; hence local clots are 

 formed which extend over the injured surface, and by a process 

 of organization, probably the repair of the denuded patch can be 

 accomplished. 



