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Dysdercus ruficollis (L. ) 
Wille et al , (98) in 1137 reported bests made with cube at the 
La Molina, Peru, Agricultural Experiment Station. In laboratory tests 
against 20 adults cf D. ruficollis, a cube dust containing 5 percent of 
rote none killed 4 and~~paralyzed "th"e others in 24 hours, and after 4 days 
19 were dead.. Dusts of lower rotcnor.e content also gave good results, 
one of 0,01 percent giving 80-percent mortality in 5 days. One unfavor- 
able resv.lt of this slow rate of toxicity was that females were able to 
oviposit normally and their eggs hatched. Sprays of 0.1 percent rotenone 
content in three tests gave 52-, 80-, and 100-percent mortality. 
Dysde rcu s supe rs titiosus (F. ) 
Andries (2) in 1932 recommended a spray of Derrisol for the con- 
trol of this cotton stainer. 
Dysdercus suturellus (K. S.), the cotton stainer 
Jaci: and Sends (45) in 1922 reported that spraying with tuba mix- 
tures is one of the means recommended for controlling the cotton stainer. 
D ysdercus sp. 
Dysd ercus sp, on cotton may be killed by spraying with derris. — 
Van der Veoht (90) in 1936. 
Eeduviidae 
Centrocnemis sp« 
Ridley (74) in 1912 wrote that in Sarawak there was a small, 
flattened, green bug, peculiar from having its sides fringed with tiny 
spines, which was identified as an immature form, probably of some 
species of Centrocnemis. The best method of dealing with this serious 
pest was stated to be spraying the vines with a decoction of tuba root 
(Derris elliptica ) . 
Tingitidae 
Corythucha arcuata (Say), a lacebug 
Hamilton (36_) in 1938 reported a kill of 90 to 100 percent of 
lacebugs on sycamore, azalea, and aster in three out of four tests made 
with a spray of derris or -cube pqwder (4 percent rotenone and 16 to 18 
percent total extractives) zt the rate of 4 rounds per 100 gallons, with 
the addition of 4 pounds of rosin-residue emulsion. The spray acts as a 
contact poison. 
Coryt hucha cydoniae (Fitch), a lacebug 
The Ohio Agricultural Experiment Station (68) in 1937 reported 
that derris-talc dust had been tested against the - Tacebug on cotoneaster 
in the laboratory but that the results obtained were not consistent. 
