REACTION OF CELLS TO CROTON OIL 229 
finally perished, and also of the epidermal cells which were lost 
at the time when the globule was extruded, there was no disin- 
tegration of cells in the inflamed area. The mesenchyme cells 
recovered completely. The leucocytes, after remaining for 
twelve hours or more in the motionless and rounded condition, 
gradually migrated away from the region. Some of them 
Vi. m 
ip? 
Ba | 
Fig.4 Sketch of the same region made June 1st, two days after the injection 
of croton oil. The opaque mass is much smaller and has shifted nearer to the 
fin margin. A number of clear leucocytes are scattered through this region. 
Several pigmented leucocytes are present, most of which have wandered out 
from the opaque mass at the site of injury. 
wandered off through the tissues, others entered blood-vessels 
or lymphatics. Two days after the injury, a number of these 
rounded leucocytes were still present in the region, and even 
after five days their number still exceeded that of the wandering 
cells present in adjoining regions. 
The small mass of debris remaining after the extrusion of the 
globule gradually diminishes in size and, at the same time, it is 
forced nearer and nearer the fin margin. During this process it 
is surrounded by some pigmented leucocytes, which appear to 
