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Silphidae 
Silpha (Blithophaga ) opaca L« 
Kumex (a proprietary product containing rotenone) was a quick 
and effective means of control of the larvae on beets in Germany. — 
Kaufmann (335 ) • 
HOMOPTERA 
Aleyrodidae 
Dialeurodes citri (Ashm.), the citrus whitefly 
Derris is toxic to the larvae.— English ( 165) • 
Aphidae 
Anur aphis roseus Baker, the rosy apple aphid 
Satisfactory control resulted when cube was used in oil in de- 
layed dormant spray.—- Steiner and Worthley ( 567 ) . 
When cube was combined with 1 pint of manniten monolaurate, fair 
control was obtained. An effective and economical combination in- 
cludes 3 pounds ©f cube in a 3-percent Goulac stock emulsion or tank- 
mixture.— Steiner (565) • 
Aphis possypii Glov., the cotton aphid, melon aphid 
On the basis of the medisl lethal dose, cube-talc dust (0.25 
percent of rotenone) was significantly more toxic to this aphid on 
okra in laboratory tests when combined with 1 percent of grppefruit- 
seed oil or soybean oil than when used alone. Likewise, the addition 
of % 1 percent of peanut or olive oil increased the effectiveness of 
the dust, but the differences were not significant,— Howard and Apple 
(293) » 
The cotton aphid and boll weevil infestations were lowest on 
plots treated with calcium arsenate plus 1 percent of nicotine. Dusts 
containing 1 percent of rotenone gave excellent aphid control in 1S41, 
but failed to control aphids in 1940. Yields of seed cotton per acre 
treated with calcium arsenate, 10 percent of sulfur, and ^r percent of 
rotenone were 1,384 pounds; with calcium arsenate alone, 1,258 pounds; 
with calcium arsenate and 1 percent of nicotine, 1,674 pounds; and 
with calcium arsenate, 10 percent of sulfur, and 2 percent of pyre- 
thrins*i 1,368 pounds. The untreated check yielded 1,2 69 pounds.— 
Becnel and Floyd (45); Floyd and coworkers (189, 190). 
