REPARATORY INFLAMMATION IN ARTERIES. 51 



a bud penetrating the latter, i. A corpuscle adherent at the 

 point of union of two adjacent endothelial cells, k. An un- 

 attached white corpuscle. a. A white corpuscle, adhering 

 tightly to the upper end of an endothelial cell {b). At tlie 

 commencement of the observation, this cell (6) was flatly 

 ai)plied to the capillary wall as the other endothelial cells now 

 are, but its upper extremity showed the slightest possible sepa- 

 ration from the lower point of the next endothelial cell above. 

 The upper point of this cell (6) appeared a little thicker than 

 that of its higher neighbor. The blood current was sluggish, 

 and at intervals interrupted. Occasionally for a few moments 

 the current would move on with considerable energy. At the 

 point of observation, besides tlie obstruction to the circu- 

 lation by the swollen endothelia, the current was impeded 

 by the adherent white corpuscles. The relative position of 

 tlie corpuscles was such that, at the time when the current 

 was forced forward with some impetus, the points of the red 

 blood disks went with considerable momentum against the 

 chink, and were violently jammed into the angle formed by the 

 upper surface of the adherent white corpuscle (a) and the 

 surface of the endothelial cell above it. In the attempt to pass 

 on, these red blood disks must perforce bend around the white 

 corpuscle (a). The tendencj' of these forces was evidently to 

 loosen and to pry out from its bed the upper end of the endo- 

 thelial cell (6). 



During an energetic increase in the velocity of the current 

 this was actually observed to take place. After that, the next 

 violent movement of the blood current sufficed to detach the 

 whole cell and to carry it oft" in advance of the other elements. 

 When tlie movement slowed again, it was observed that the 

 place of former attachment of this cell (6) was void of its 

 endothelial covering. I have observed the above-described 

 phenomena on one other occasion. 



Xow any one who carefully examines the course of cnpilla- 



