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A dust containing 2 percent of rotenone killed none of the active red 
spiders on beans growing in a greenhouse. 
Davidson (52) in 1930 compared the value of aqueous suspensions of rotenone, 
deguelin, tephrosin, and toxicarol when used against insects living. on potted 
plants in a rreenhouse. ' Their relative contact insecticidal value was in the 
order given, rotenone "being the most potent. An aqueous suspension of rotenone 
(l:?P00) killed 6o„7 percent of the red spiders on beans. Deguelin and 
toxicarol at the sane concentration killed 10 and 18 percent, respectively, 
and Tephrosin at 1:5,000 killed 10 percent. 
The Florida Agricultural Experiment Station (62) in 1931 reported that 
Derrisol has been found to be an effective spray for the green mite on 
Asparagus p lumosus . 
Yothers and Keck ( 172 ) in 1930 reported that sprays containing 5 percent 
of derris extract were more effective than those containing nicotine sulfate, 
kerosene emulsion, lubricating-oil emulsion, or pvrethrum extract in controlling 
the red spider on asparagus pluxr.'cus in Florida fernorie's.. Derris spray kill? 
very slowly and very little mo.rtaxity is obtained in 4 or 5 hours. In some 
cases it is greater in 48 hours than in 24. 
Compton (44) in 1931 recorded tests with Derrisol and rotenone against the 
red spider in greenhouses, Derrisol in a concentration of 1:400 killed from 
72 to 81 percent of red spiders on greenhouse plants. When Penetrol in a 
concentration of 1;200 was added to this solution from 98 to 100 percent of 
the red spiders were killed. Penetrol containing 0.1 gm. of rotenone per 100 
cubic centimeters at a dilution of 1:100 (equivalent to 1:100,000 of rotenone 
killed from 58 to 64 percent, Derrisol at 1:400 combined with Penetrol at 
1:200 killed from 87 to 93 percent of the eggs of the red spider. Mixtures 
of Der.'-;sol and Penetrol in other proportions were less effective. The 
mortality figures are based on the number that were dead at the end of 24 hours, 
as no appreciable increase in percentage of kill was observed after this 
period. Commercial tests with this mix-ture were made in eight greenhouses in 
Cook County, 111. , and excellent control of red spiders was obtained with two 
applications made 8 days apart. 
Darle.y (49) in 1931 reported comparative tests with rotenone, nicotine, 
and pyrethrum on the common red spider. Rotenone was used in the form of a 
solution consisting of. 0.2 ■ gm. of rotenone, 5 cubic centimeters of benzol, 
and 95 cubic centimeters of Penetrol. Rotenone at 1:50,000 killed 89. 8 
percent of the common red spider. The check mortality was 6.4 percent. 
Jones and Davidson '(82) in 1931 reported that rotenone and derris extracts 
prepared with fish oil have a high toxicity to red spiders. 
Little (93^) in 1931 gave a detailed account of the insecticidal properties 
of devil 's-shoestrings. .Dried and powdered (100-mesh) roots were suspended 
