- 12 - 
Smith and Scales (8_l) in 1937 reported the foil-owing results of 
insecticidal tests on L. prat ens is confined in cages on cotton: 
Materials and proportions 
Pyrethrum-cube-sulSur 10 :1G : 30 
( rotenone 0.49 percent)- - - - 
Pyrethrum-sulfur 40-.-60 ------- 
Pyre thrum (0.76 percent total 
pyrethrins)? - - - - 
Sulfur 
Checks --------------- 
Cube-pyrethrum 40:60 (rotenone 1.96 
percent)- - 
Cube- sulfur 20:80 (rotenone 0.98 
percent)- - 
Cube-sulfur 10:90 (rotenone 0.49 
: J 
: Nymp 
ortf 
hs 
ility 
Adul 
ts : 
Kymr 
Cor 
>hs 
r.t 
it 
rol 
adults 
Perce 
nt 
Perce 
nt 
Perce 
P 
ercent 
79 
52 
71 
21 
74 
78 
63 
63 
90 
83 
86 
SO 
70 
41 
58 
3 
29 
40 
— 
— 
percent)- - 
54 
Cube (rotenone 4,9 percent)- 
49 
33 
12 
50 
Derris dusts gave promising results against L, pratensis on 
chrysanthemum. A dust containing sulfur, derris, and nicotine seemed 
to be superior to one containing derris and nicotine and also to one 
consisting mainly of derris. — [Cheshunt] Experimental and Research 
Station (12) in 1938. ...-•■■ 
Smith, Scales, and Gaines (82) in April 1S39 reported tests made 
at Tallulah, La., in 1938 with insecticides on caged cotton plants out 
of doors. In tests against adults of the tarnished plant bug, derris 
containing 4.3 percent of rotenone was only slightly more effective than 
when diluted with sulfur to contain approximately 1 percent of rotenone, 
while both the derris and. the derris-sulfur mixture were more effective 
than sulfur alone. 
The same authors (83) in December ! r 39 reported the results of 
tests against L, pratensis adults with derris as follows: 
