-42- 
DeBussy, van der Laan, and Diakonoff . ( 57 ) In 1936 reported that in 
the Netherlands derris was the best material .for the control of this 
species. The rotenone content should be at least 0.5 percent and, pref- 
erably, 0.75 percent. The dosage was 50 to 75 kg. per 10,000 m£. 
The Koloniaal Instituut ( 240 ) in 1936 reported that in the Nether- 
lands an example of the practical use of derris is the control of this 
insect. in Groningen. Eighty-six thousand kg. of derris dusting mixture 
was used in 19 35 for control. Derris was first applied as a dust in 1934 
and pure rotenone was also used in 1934. 
The destruction of the caraway moth by means of derris has become a 
general practice in the Netherlands. — Koloniaal Instituut of Amsterdam 
( 259 ) in" 1936. 
In the Netherlands, one of the principal uses of derris is to control 
this insect. — Van der Laan ( 244 ) in 1936. 
An anonymous writer (5) Virrote in 1937 -.that in the Netherlands the 
caraway moth was effectively checked with a derris dust containing 0.75 
percent of rotenone. 
The Koloniaal Instituut ( 241 ) in 1958 reported that in the Nether- 
lands derris dusts containing 0.5 to 0.75 percent of rotenone were large- 
ly used for combating the caraway moth. ) 
Hofmannophila pseudospretella (Stt.) 
An anonymous author (5) in 1937 wrote that the larvae of ( Bo rkhau - 
senia) Hofmannophila pseudospretella were sensitive to derris dust con- 
taining 1 percent of rotenone. 
Olethreutidae 
Ancylis comptana f rap;ariae (Walsh & Riley), the strawberry leaf roller 
At the 1934 meeting of the American Association of Economic Entomol- 
ogists, as reported by the United States Department of Agriculture, Bur- 
eau of Entomology and Plant Quarantine ( 437 ), Cory led a discussion of 
field results with arsenical substitutes for the control of vegetable' 
insects. Hutson, of Michigan, reported" that derris dust containing 0.5 
percent of rotenone had been most satisfactory for the control of the 
strawberry leaf roller. Satisfactory diluents were flour, talc, bentonite, 
china clay, 300-mesh dusting sulfur, tobacco dust, silicated infusorial 
earth, and finely ground gypsum. 
In 1934 the Michigan Agricultural Experiment Station ( 275 ) reported 
that an infestation when there wore berries on the plants was best con- 
trolled by the uso of pyrethrum or derris ducts or sprays. 
