740 Report oF THE ENTOMOLOGIST OF THE 
purple, both prepared according to formula given for water mix- 
tures of Paris green and London purple on page 763 of this report, 
except that one-third pound more of each poison was used. Each 
plat contained about an equal number of heads of the smooth 
and curled varieties. The mixtures were applied with a knapsack 
sprayer which has no agitator.. The mixtures settled some, so 
that the first heads sprayed in each case were thoroughly smeared 
with the lime and arsenites. 
September 28. No signs of injury by burning on any of the 
plants. In both cases more of the European cabbage butterfly 
caterpillars are dead than of the Cabbage-moth caterpillars. 
October 2. No injury to any of the plants sprayed September 
25. Some lime still adheres to the plants after a heavy shower 
of the 29th. 
A series of tests made in the laboratory by simply spraying 
the leaves of cabbage with an ordinary atomizer, showed more 
conclusively than the field test that lime aids the mixture in 
adhering to the foliage, as well as preventing injury by burning. 
October 2. While the cabbage was covered with dew about 150 
heads were dusted with Paris green, one part to 15 parts flour. 
Treated same number of heads with London purple, one part to 
15 parts flour. Applied the above powders with a “powder 
gun,” as thick as “slug shot” is usually applied. Each plat con- 
tained an equal number of smooth and curled varieties. 
October 6. Leaves of both varieties of cabbage burned in both 
plats. The Savoy variety injured the worst. 
October 17. Repeated experiment of October 2 under same con- 
ditions, except that the dew was off. 
October 19. Light shower. 
October 22. Each patch is burned slightly, especially the Savoy 
varieties. | 
It follows without proof that neither flour nor road dust will 
prevent free arsenic in Paris green or London purple going in 
solution if applied while the dew is on, and if applied when the 
plants are dry it adheres to the upper surface of the leaves and is 
no more efficient than when applied in water alone at least 
against the cabbage moth. 
Some of the market gardeners use Paris green as strong as 
one pound to 80 gallons of water for potatoes. There is no danger 
