~llU- 
Walker ( U65 ) in 1937 reported the results of tests of cube dusts 
(0»75 percent rotenone) and sprays (3 lb. per ICO gal.) to control the 
imported cabbage worm, both with and without Ultrawet. In most instances 
the addition of Ultrawet did not result in increased protection of the 
plants. 
Wisecup ( U90 ) in 193& reported that at Sanford, Fla. , a cube-dust 
mixture containing 0.055 percent of rotenone was very effective in kill- 
ing quarter-grown larvae of the imported cabbage worm, and this dilution 
is the most suitable of any tested for use in obtaining comparative re- 
sults of the reactions of insecticides to larvae of ?. rapae . In 1938 
V/isecup/T'lpOTted that insecticidal dusts made from the powdered roots of 
Derris elliptica , Lonchocarpus sp., and Tephrosia virginiana , diluted 
with clay to con+ain uniform percentages of rotenone, were tested in the 
laboratory against larvae of this species. For each material used, ISO 
uniform quarter-grown and an equal number of half-grown larvae were used. 
There was no significant difference in insecticidal efficiency between 
the averages of derris and of cube powders containing nearly equal per- 
centages of rotenone and total extractives. One sample of cube, however, 
was definitely inferior, contrary to what would have been expected from 
the Shemical analyses. Samples of T. virginiana diluted 1:3 with clay, 
with resulting rotenone contents as low as 0,0 ] 42 percent, were so toxic 
to quarter-grown larvae that no comparisons could be made. The same 
dilutions of Tephrosia tested with the more resistant half-grown larvae 
did not differ significantly among themselves except for the sample 
ground coarser than 60 mesh, which was inferior to the best. The best 
saimle of diluted Tephrosia was not inferior to a derris dust containing 
0,5 percent of rotenone and v/as superior to one containing 0.1 percent. 
Materials were diluted with clay to contain 0.1 percent of rotenone for 
tests with quarter-grown larvae and 0.5 percent of rotenone for half- 
grown larvae. 
T ; T isecup and Reed ( hyk ) in 1938 reported on a study of the decrease 
in effectiveness of cube when exposed to weathering in Florida. The 
source of rotenone in the first six tests was sample of powdered cube 
root containing 6 percent of rotenone and 20.5 percent of total carbon- 
tetrachloride extractives, whereas that in the last two testr was a differ- 
ent sample of powdered cube root containing 6.9 percent of rotenone and 
only 15*9 percent of total carbon-tetrachloride extractives. Four of the 
treatments in each test were apolied as sprays and four as dusts, with 
one untreated control. The dusts were always mixed in the proportion of 
1 part of cube to 9 parts of diluent. The diluents were talc, clay, to- 
bacco dust, and sulfur purchased from local distributors. The B 
were made up to contain 2 pounds of cube per 50 gallons of water, and the 
adherent or spreading agents added at the rate of 1:S00, or 1:500, the 
quantity being kept constant in any one test. The proprietary spreaders 
or adherents used were: (l) A sulfonated, partly oxidized, petrol* 
hydrocarbon, (2) alkylp&enylbenzcnesulfonic acid, and O) calcium cast i- 
nate. Eight combinations of cube were applied to cabbage in the field and, 
after 5 days of exposure to weathering, samples wcr. fod to imported cab- 
bage worms under controlled laboratory conditions to obtain r< Lativc mortal:- 
ty records. Eight replicates of each of these tests »erc made unci sly 
different weather conditions. There was a uniform decrease in mortality 
