6 ^ 
Fall webworms: These caterpillars, Hyphantria cunea Drury, alDout 
one-third grown, were killed within a week "by a spray containing 1 pound 
of powder to 5 gallons of water. Mixtures ranging from 1 pound to 50 
gallons to 1 pound to 200 gallons were not satisfactorily effective, since 
nearly all the sprayed foliage was eaten and not all the caterpillars were 
killed. 
Oak v7orms: Two small oak trees, on which about 300 caterpillars of 
Anisota senatoria A. and S., were feeding, were spraved thoroughly with 
derris at the rate of 1 pound of powder to 25 gallons of water; soap was 
added at the rate of 1 pound to 50 gallons, and a knapsack sprayer was used. 
Within 24 hours the larvae hecame inactive and ceased to feed, and at the 
end of 6 days no living ones could "be found. As a check on this test, 
powdered lead arsenate was applied at the rate of 1 pound to 50 gallons 
of water, and almost identical results were obtained. 
A second test was made in which a small tree was sprayed, and 24 
hours later about 50 larvae were placed on it. The caterpillars ate very 
little and gradually disaiopeared, evidently leaving the tree, since no 
dead ones were observed; and at the end of 5 days they were nearly all 
gone. 
Datana larvae: Two apple trees, on which large colonies of nearly 
full grorm apole datanas, Datana ministra Drury, were feeding, were sprayed 
with derris at the rate of 1 pound of powder to 50 gallons of water. 
Twenty-four hours later one living larva was found one one tree and two 
on the other. The ground under the trees was thickly sprinkled with 
dead larvae and many had lodged in the trees. 
Cabbage worms: In two cage tests against cabbage loopers, Auto - 
grapha brassicae Riley, derris, applied at the rate of 1 pound to 25 gallons 
of water, killed all the larvae within 24 hours. 
Howard (97), in his 1S19 annual report as Chief of the Bureau of 
Entomology, United States Department of Agriculture, stated that if derris can 
be obtained in sufficient quantities, it will prove an important addition 
to our list of substances that kill soft-bodied insects, such as plant lice. 
Roark (81) in 1919 included Derris elliptica and D. uliginosa in a 
list of insecticidal plants. 
1920 
Mathieu (62) in 1920 reported the control of Agromyza phaseoli Coq. 
attacking young beans, with derris. 
"A trial of tuba was made on a field of 8 beds, 66 feet long, 
with 1,056 seeds of Lima Bean (Small Sieva) on the 28th of October, 
1919. Ten ounces of tuba-root were well pounded in a wooden 
mortar, the juice was thoroughly expressed, and the fiber exhausted 
in 20 imperial gallons of water. Tuba-water was then applied to 
