242 ELIOT R. CLARK AND ELEANOR LINTON CLARK 
THE BLOOD-VESSELS 
The blood-vessels situated in the area in which the connective- 
tissue cells became vacuolated showed definite signs of injury. 
The endothelial cells became vacuolated and the nuclei became 
more prominent within a few minutes after the injection. The 
vessels became constricted and the circulation ceased about a 
half-hour later. At some points these vessels constricted until 
they consisted of a solid hyalin thread. At other points they still 
a 
Fig. 12 Drawings showing three successive stages in the movement of the 
two cells g and h, which are shown in the first stage (10:30 A.M.) in figure 11. 
The marked reduction in length of processes dur ng this (relatively) rapid move- 
ment is particularly noticeable in the last stage (11:30 P.M. and 10 P.M., respec- 
tively). O.G., oil globule. 320. 
contained red blood-cells and leucocytes. There was no migra- 
tion of white blood-cells from the vessels within the ‘granular’ 
area. Outside this region, the blood-vessels showed the typical 
changes of inflammation, acceleration in the flow followed after 
about an hour by a slowing of the current and diapedesis of 
leucocytes. Inside the ‘granular’ area the frequent occurrence 
of hemorrhage gave further evidence of injury to the vessel wall. 
And twenty-four hours or more after the injury, a retraction of 
one or more of these blood-vessel sprouts or loops located within 
