THE BAGWORM. ii 
we consider an unnecessary expenditure. Moreover, if two or three 
applications are made—and this is often desirable in case this or other 
insects continue to injure the trees—it is almost certain to affect inju- 
riously or destroy some forms of tender leafage if made at this 
strength. 
The best time to apply either of the arsenicals mentioned, as in the 
case of most insects, is at about the time when the eggs hatch or a 
day or two afterwards. 
