232 ELIOT R. CLARK AND ELEANOR LINTON CLARK 
a short distance of the croton oil. The first processes sent out 
are fine and hair-like. These streamers are withdrawn and sent 
out again, thus changing the contour of the cell frequently. 
After a few hours these processes become reduced in number, 
ee ee ee 
1228 1235 
1254 115 130 137 _ 
6 
gis Fe re Es 
/040 Ti35: EE 1225 
}00 {375 900 250 
7 
Fig.6 Series showing changes in a single leucocyte which has emigrated 
from a blood-vessel and become stationary near the site of injection. 21X83. 
Fig. 7 Series showing the changes undergone by a sessile leucocyte, situated 
near the injected site, for a time before and after the extrusion of the croton oil. 
At 11:45 the oil globule was very superficial and the connective-tissue cells of 
the region had begun to show signs of recovery. At 1:25 many of the nearby 
leucocytes were amoeboid. At 2:30 all the clear leucocytes had rounded up. 
The pigmented leucocytes were wandering around actively. The connective- 
tissue cells were changing and moving toward the site of injury. At 4:00 the 
clear leucocytes of the region were still motionless and spherical. 133. 
400 
larger, and more stable, and the cell then resembles a small 
immature connective-tissue cell. 
Metchnikoff (’93), in his account of inflammation in the | 
tadpole’s tail following a burn with silver nitrate, described the 
