8 
still, it prevents any great damage, and insects thus poisoned are out 
of the way for good, both as regards future damage by the individual 
and by its otherwise possible offspring. 
When the idea of poisoning the tobacco leaf was first suggested it 
met with considerable opposition. It was feared that the persistence 
of the poison might render the tobacco dangerous to the human con- 
sumer. This fear still exists in many quarters; in fact, the average 
smoker, and, still more, the average chewer, would hardly faney the 

Fia. 4.—Northern tobacco worm, or ‘‘horn worm” (Protoparce celeus): a, adult moth; b, full- 
grown larva; c, pupa—natural size (original). 
idea that his tobacco had, at any time, been treated with arsenic. 
The same feeling, however, existed when Paris green was first used 
on the potato crop for the Colorado potato beetle. It was expressed 
when fruit growers began to spray apple trees for the codling moth, 
and it still remains in regard to the use of arsenicals upon eabbages, 
in spite of the fact that most cabbage growers are using them, and 
that it has been repeatedly shown that the quantity of poison which 
is effective is so infinitesimally small that not the least possible harm 
can result to the consumer. The same holds with regard to tobacco. 

ES ——=— 
