-79- 
Erythroneurfi spp., grape leafhopper3 
Sprays containing pyrethrum or derris, or their extracts, are 
sometimes used for control.— Deraaree and Runner ( 139) . 
For control of grape leafhoppers use pyrethrum extracts in con- 
centrated form applied in vaporized oil; rotenone extracts applied 
as sprays j or calcium cyanide, as dust.--U. S. Department of Agri- 
culture (633 , p. 12). 
Evacanthus interruptus (L»), a hop leafhopper 
Populations of this pest on hops in England were greatly re- 
duced following two applications of a derris dust.— Massee (399). 
Macrostelos divisus (Uhl.), the six-spotted leafhopper 
This inseot transmits the virus of eastern aster yellows to 
endive and lettuce. Dusting with a mixture of pyrethrum and sul- 
fur containing at least 0.15 percent of pyrethrins, or with derris 
and sulfur (l percent of rotenone) at weekly intervals from trans- 
planting time to harvest gave significant decreases of diseased 
lettuoe plants.— Linn (365). 
Ophiola sp., the blunt-nosed leafhopper 
Derris dusts (l and 1.5 percent of rotenone) with camphor oil 
and peanut oil, respectively, as the activator and wetter, applied 
once at 95 and 100 pounds per acre, both gave at least 94 percent 
mortality. Results of commercial control of this jassid have in- 
dicated that treatment should be carried out thoroughly when more 
than 3 leafhoppers ar# taken by 50 sweeps of an insect net.— Franklin 
(193). 
Typhlooyba roaae (L.), the rose leafhopper 
The controls recommended in Germany against this pest on apples 
were a dormant spray of tar distillate, a lime-sulfur spray, or 
mixed dusts of derris and pyrethrum.— Voboril (640) . 
Unidentified ?.eafhoppers 
Rotenone was considered fair, while copper-rot en one was good 
for leafhoppers in victory gardens in Indiana.— Reed (496) . 
Pyrethrum can be substituted for rotenone for the control of 
leafhoppers.— Turner and Horsfall (606) . 
