380 Report oF THE ENTOMOLOGISTS OF THE 
About 300 caterpillars included in 3 nests were used in these ex- 
periments. The first application was made May 22, the second 4 
days later and the third 7 days from the time of the second appli- 
cation. At the time of the first application the caterpillars were 
less than half grown. ie 
Paris green.— Similar experiments were made with Paris 
green. It was applied in the same proportion and at the same 
time as the green arsenite. 
Results.— Four days after the first application nearly all of the 
caterpillars were sluggish. Within 3 days after the second . 
application only a few live worms could be found. ‘The third 
application was hardly needed. . Where the Paris green was 
evenly applied there was no.apparent difference between its effects 
and that of the green arsenite. 
Hxpervments in 1898. Green arsenite-— About 200 worms, 
from 2 nests, were used and the green arsenite applied twice 
in May at intervals of ten days. The "green arsenite was 
mixed with lime water in the same proportion as in 1897. No 
Paris green was used. 
Arsenite of lume.— (For formula see page 388 of this report.) 
Similar experiments were conducted with arsenite of lime, the 
applications being made at the same time. 
Results—— The effects were practically the same in both in- 
stances as with the poisons used the year previous. 
Conclusions.— The above indicates that the 3 arsenicals used 
may be depended upon to kill the caterpillars if applied early 
enough. ‘The first application should be made before the cater- 
pillars are half grown. _ ; 
Destroying the caterpillars in the nests.— This is done in a 
variety of ways. Any way that is thorough and convenient and 
does not result in injury to the tree will answer. It is only neces- 
sary to be prompt and thorough. A common practice is to pull 
out the nest with the gloved hands and destroy the caterpillars. 
Others practice burning the nests with a torch or pouring kerosene 
upon them. 
