-98- 
Parts by weight 
Ground cube or derris (5 percent of rotenone)— — 1 
Pyrophyllite (90 percent to pass through a No. 32 5 
soreen) — — 2 
The following spray formula at 400 pounds 1 pressure was 
found satisfactory: 
Cube or derris powder (6 percent of rotenone)—— 7«5 pounds 
The following wash formula is recommended: 
Ground cube or derris (5 percent of rotenone)— 12 «0 ounces 
Granular laundry soap———————————— 4.0 ounoes 
The following formula is used for dips: 
Ground cube or derris (5 percent of rotenone)—— 10,0 pounds 
"Wetting agent (sodium lauryl sulfate)- — — — — — 2,0 ounces 
Water 100.0 gallons 
— U. S* Bureau of Entomology and Plant Quarantine (631 ) . 
Itonididae 
Contarinia hurouli T$lg», hop strig maggot 
Satisfactory control was given in tests in which derris and nico- 
tine dusts were applied against the adults on hops in England in late 
July. A derris dust was later applied to the soil just before the 
larvae left the cones.— Masse 9 (400 , 402 ) . 
Contarinia pyrivora (Riley) , the pear midge 
In Denmark the measures adopted against the adults included fou 
applications of a niootine spray, and dusting thd pear trees and soi". 
with derris •--Bovi en (77). 
Dasyneura mall Kieffer, the apple leaf-curling midge 
Good control was secured with sprays containing 3 pounds of fixed 
nicotine or 5 pounds of ground derris.— Parrot t (457) • 
