1387) oo a ntomology. ; 481 
entomologist of Illinois Professor Forbes gives the results of a 
series of experiments made by him to test the efficiency of ar- 
' senical poisons in the protection of apples from the codlin-moth. 
seventy-five thousand dollars. He then goes on to show that at 
least seven-tenths of this loss may be prevented by a single re- 
medial measure so simple that any one may apply it, and without 
cost so far as its effect on the codlin-moth is concerned. 
efficient as Paris green; and the leaves on the trees which were 
sprayed with arsenic were scorched, while those to which Paris 
green was applied were entirely uninjured. : 
The time of year at which poisoning is most effective is in the 
spring, after the apples have begun to form, and while they are 
still upright. The poison lodges in the calyx, where, as is well 
nown, the egg of the codlin-moth is laid. The young larva is 
thus poisoned as soon as it begins to eat its way into the apple. 
Later in the season, after the apples have begun to hang down- 
wards, spraying will not deposit the poison where it will be 
reached by this insect. Moreover, it is dangerous to apply the 
poison late in the season, as it will lodge in the cavity about the 
stem of the apple, a position from which heavy wind and violent 
_ rain are not sufficient to remove it. 
The results of his experiments are given by Forbes with con- 
siderable detail. They show that by spraying once or twice with 
Paris green in early spring, before the young apples had dropped 
upon their stems, about seventy-five per cent. of the apples ex- 
posed to injury by the codlin-moth were saved. The incidental 
benefit to the crop in the protection of the trees against foliage- 
or ba 
eating insects, and also against the Apple Curculio, by thus — 
