80 
of April, and, when placed in the cage with opening apple buds, nibbled 
a little, but almost immediately changed to pup within a cluster of 
webbed leaves. Pupa smooth, dark brown, without any especially dis- 
tinguishing characters. Three imagines appeared April 24. They were 
of a species which had been long before determined for me as a Palthis 
angulalis. 
With the idea that possibly the immature stages of this insect had 
not previously been observed, I submit the above descriptions. 
INSECTICIDES. 
White arsenic in ammoniacal solution—1 ounce arsenic to 1 quart aqua 
ammonia—one tablespoonful of this to a gallon of water proved a 
failure in the case of most insects, while it still scorched the leaves 
somewhat. 
A soda solution made on a smaller scale had much the same effect on 
the foliage of peach and plum trees, and was not, so far as could be 
observed, efficient in protecting the fruit from cureulio. 
White arsenic in boiling water, the latter being only a partial sol- 
vent, in the proportion of an ounce of arsenic to 20 gallons of water, 
was sprayed upon young peach and plum trees without injury to the 
foliage. The frequent rains of the late spring and early summer ren- 
dered many of the applications futile in the case of the curculio and cod- 
ling moth. Paris green in liquid, 1 pound to 100 gallons of water, has 
been found the safest and most reliable insecticide for use against 
the canker-worm and codling moth. Its effects on insect life seem to 
be due not alone to the percentage of arsenic, but to the general com- 
bination, while on vegetation it produces less injury than London pur- 
ple or any of the solutions of pure arsenic. 
In my somewhat limited experience the petroleum emulsions can not 
be excelled as a remedy for all species of scale insects, and when ap- 
plied according to instructions, do no appreciable injury to trees and 
shrubs. 
X. O. Dust.—Late in May I received from the Department a package 
of this new patented insecticide, with instructions to test its value on 
various injurious insects. It is to be applied full strength and claims 
to kill by contact and at the same time to be innoxious to man and the 
higher animals and to vegetable life. 
June 1.—Applied the powder about 9 o’clock in the morning to Dory- 
phora larvee on potato, to late specimens of the rose-slug (Selandria 
ros), to Aphis persice on young peach and plum trees, and to Aphis 
sp.? on chrysanthemums; also to young cabbages and radishes, on 
which flea beetles (Phyllotreta vittata and zimmermanni) were abundant 
and destructive. Three hours later visited these plants and noted fol- 
lowing results: Rose-slugs considerably affected, showing symptoms of 
sickness and paralysis and dropping from the leaves when jarred. 
Doryphora larvie not seriously affected, only the smaller ones had 
dropped, while some of those nearly grown continued feeding, appar- 
