-68- 
Rotenone and copper-rotenone were considered poor for blister 
beetles in victory gardens in Indiana.— Reed (496) • 
A talc-rotenone dust containing 2 percent of rotenone was tried 
against 7 species of blister beetles in Arkansas • -• -Horsf all (290) . 
Nitidulidae 
Meligethes aeneus (F*), a rape beetle 
In England two applications of derris dust failed to protect 
seed crops of swedes and kale, and four applications increased the 
crop only slightly* In tests under insectary conditions, mortality 
caused by derris after 6 days was 85*0, 62*5, and 82*5 percent* The 
general effect was that of a repellent*— J ary and Austin (320 ) » 
Derris dusts were effective and some were inexpensive against 
rape in Germany* In dry weather their toxic effect oontinues for 
3 days but a 0*2 ^noh of rain washes off the dust* In one test, 10 
applications of Kumex (0»8 peroent of rotenone) were necessary owing 
to bad weather but even so, the measure was profitable*— Blunok and 
Meyer (59) • 
In Germany the best results were given by Kumex which gave com- 
plete mortality in 24 hours in the laboratory, and reduced the in- 
festation on rape in the field by 90 to 96 peroent in the same period* 
In one field the dust was still effective 6 days after application* 
—Prey (200). 
In view of the good results given by Kumex, -tills material and 
another proprietary derris dust (L) with the same rotenone content 
were applied in East Holstein. Kumex was satisfactory when applied 
to 200 aores of rape at the rate of 22*5 pounds per acre* Infes- 
tation was decreased by 90 peroent 1 day after treatment* Kumex al- 
ways gave good results, but the other derris dust was completely in- 
efficient*— Gof fart and coworkers (234 ) • 
Kumex is widely used in Germany for control of the rape beetle, 
but it is not usually applied after the plants begin to bloom for 
fear of poisoning honeybees* Experiments were therefore carried out 
to test the necessity for this precaution* The dust was applied at 
unusually high rates and the bees suffered no harmful effect*- 
Kaufmann (336). 
An attempt was made to find a substitute for Kumex which had 
been found effective against the rape beetle in Germany* In the 
laboratory Kumex gave 100 peroent mortality in 2 days when undi- 
