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If much of our testimony on the subject of insecticides seems to 
the reader non-committal, we can only remind him that one season is 
not long enough to make conclusive experiments, unless we are fully 
decided beforehand upon our point of attack, and this, to the experi- 
menter, is often impossible. 
One of the first insects with which we have to contend in spring is 
the cabbage flea beetle, Hallica striolata. This is the spry, little, dark- 
brown beetle that is so destructive to the young plants of cabbage, 
radish and turnip. Strange to say, Paris green mixed with plaster in 
a quantity that is doubly sufficient to kill the potato bug has no effect 
upon this insect. It seems probable, therefore, that it does not eat the 
epidermis of the leaves. We found, however, that strong tobacco 
water either destroys it or drives it away from the plants. The de- 
coction of tobacco must be as strong as it can be made by soaking the 
leaves in cold water, or it will not avail. We mention here that hot 
(not boiling) water extracts more of the-strength of the leaf than cold 
water. 
With the striped cucumber beetle, Diabrotica vittata, Fabr., tobacco 
water was of no avail. We found, however, that Paris green mixed 
with ground limestone at the rate of one part to one hundred, by 
weight, was in a degree efficacious. We tried placing corn cobs dipped 
in coal tar about the plants, and also cobs dipped in kerosene oil, and in 
turpentine. These noxious substances had some effect in driving off | 
the beetles, but were not entirely effectual. 
We have this insect to battle in two forms. Its larva, in'the shape 
of asmall white grub, attacks the root of the plant, girdles it, and 
sometimes perforates it with holes.- This is what so often causes the 
young plants of cucumber and melon to shrivel and die soon after 
the first leaves are dey eloped. We found that Paris green mixed with 
water at the rate of an ounce to three or four gallons, poured about 
the stems of the young plants seemed to prey ent the grubs getting a 
foothold, when the plants were not already infested. It did not, how- 
ever, destroy the grubs inside of the stem. It will not answer to wait 
until the shriveled foliage tells that the stems are already infested. 
In applying the mixture to the stems, were moved carefully, with a 
trowel, about an inch of the surface-soil about the plants, poured the 
poisoned water about the stem from the spout of a sprinkling pot, and 
replaced the soil. Itis best to do this in the evening, or on a wet 
day. As this insect is the larva of the striped bug, we may expect to 
meet it wherever the latter abounds. It should not, however, be con- 
founded with the squash-vine borer, Melittia cucurbita, L., which is a 
different insect, and of which we shall treat later. 
We found that one pound of Paris green, thoroughly mixed with — 
two hundred of ground limestone, is quite efficient in destroying the 
larvee of the potato beetle, Dora yphora decemlineata, Say. We had 
formerly used one part to one hundred. Our experiments show that 
we may reduce the cost and the danger of applying Paris green for the 
potato bug one-half. We would emphasize the importance of thorough 
mixture, however, where so small a proportion of poison is used. 
Ground limestone has about the same specific gravityas common land 
plaster, and the latter would doubtless answer as well. 
Next in order of the season comes the cabbage caterpillar, the larva 
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