- 41 - 
After adjusting the airplane spraying equipment so as to produce a 
fine fog, 1 gallon of pyrethrum-derris concentrate to 30 gallons of oil 
reduced the aphid population 40.1 percent. A later court indicated a 
reduction of 71.4. percent. Nicotine (l gallon of 50 percent free nico- 
tine to 27 gallons of oil) reduced the population in the two counts 68.3 
and 94.5 percent, respectively. 
Smith ( 244 ) in 1937 reported that derris powder (4 percent rotenone) 
at 2 pounds per 100 gallons of water plus l-l/4 pounds (dry "basis) coconut- 
oil soap or l/2 pound Dry Aresket 300 caused a reduction of 96.5 percent 
in the population of pink and green potato aphids on tomato plants. 
Counts were made at the end of 24 hours. 
Craufurd-Benson (57) in 1938 experimented with M. solanifolii 
collected in the field as a test insect for determining the value of liquid 
contact insecticides, especially derris preparations, but found the results 
to be completely unreliable. 
Gunderson (134) in 1938 recommended derris against potato aphids. 
Cube or derris dust is ineffective, — Eaude ( 144 ) in 1939. 
Macro si phum rosa e (L.), the rose aphid 
Mclndoo and Sievers ( 18 8 ) in 1924 repcrted that a cold alcoholic, 
and also a benzene extract of cube were effective when used with soap. 
TTeoton (derris extract in fish oil) 75 gm. plus twice its weight 
of soap in 40 imperial gallons killed 100 percent. — Institute of 
Physical and Chemical Research ( 162 ) in 1927. 
F'oliafume (a pyrethrum-derris spray with spreader) at 1:400 killed 
94 percent in 48 hours. — Penick and Company (223) in 1936. 
A bed of about 40 rose plants infested with M. rosae was divided 
into two parts and sprayed with 0.25 and 0.5 pint of commercial acetone 
derris extract containing 5 percert of rocenore per 100 gallons, respec- 
tively, 0.2 percent of soap being used in each case. Complete control 
of this insect was obtained with the 0.5-pint concentration and about 
80 to 90 percent with the 0.25-pint spray mixture. — Cdnsburg and 
Granett (124) in 1935. 
Siphoncpho ra Macros iphum rosae (L.) is killed by a proprietary 
dust containing 12 percent of cube of 6 percent rotenone content. — 
Etablissements Eotenia in a letter to P.i C. Roark in 1938. 
Macros iphum rudbeckiae (Fitch), the goldenglow aphid; or cone flower aphid 
Darley (6J2) in 1931 reported comparative testr with rotenone, nico- 
tine, and pyrethrum on aphids. Rotenone was used in two stock eclutions, 
one consisting of 0.2 gm. of rotenone, 5 cc. of benzol, and 95 cc. of 
Penetrcl; the other of 1 gm. of rotencne in 50 cc. of acetone. A few 
preliminary tests again:;t M. £j££t> ec 1 c i ae_ on goldenrcd gave the following 
results: Black" Leaf 40 at 1:1,000 (nicotine 1:2, 500 ) produced a 
