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Merino and Otanes ( 273 ) in 1938 recommended derris powder for dusting 
and spraying against cabbage caterpillars, except this cutworm. 
Frodenia sp. 
Derris spray is not effective against Frodenia larvae. -- Deli Proef- 
station (94) at Medan, Sumatra, in 1939. 
Spodoptera mauritia (Boisd, ) 
The Federated Malay States Department of Agriculture ( 123 ) in 1934 
reported that during the previous year 78 spraying experiments, 9 dusting 
experiments, and 145 other experiments with derris extracts had been car- 
ried out. Spraying and dusting experiments were made on 6,010 larvae of 
this species. These insects thrive well in captivity and are easily ob- 
tained when the question of replenishment of stock arises. 
Spodoptera pec ten Guen. 
Miller (279) in 1935 published a report on the toxic value of differ- 
ent species of Derris, describing 347 tests in which aqueous solutions, 
extracts, and dusts of 3 types of Derris root and 3 constituents of derris 
vrere tested against several species of insects and against fish and rats. 
The samples consisted of Derris elliptica grown at "two localities and of 
D. malaccensis var. sarawakensis. The D. olliptica from one locality had 
a higher rotenone and ether-extract content than that grown at the other. 
In the D. m alaccensis var. sarawakensis the rotcnone content was low but 
the ether extract was high. One of the principal test insects was the lar- 
va of the noctuid moth Sp odoptera pecten. Stock solutions of the 3 kinds 
of derris roots were prepared at the rate of 75 gm. of fresh root per liter 
of water, this amounting to from 21 to 29 gm. of dry root per liter. These 
solutions were preserved by the addition of formalin. By the addition of 
barium hydroxide or calcium hydroxide to these aqueous solutions the solids 
vrere precipitated. This sludge, when dried and powdered, was used in the 
dusting experiments. The insect tests vrere made by spraying, dusting and 
immersion. In most of the tests the mortality counts were based on exami- 
nation of the insects on the third day after the test. The results of the 
spraying and immersion tests indicated that the insecticidal properties of 
the 3 kinds of derris tested wore about the same. The conclusion was 
drawn from these tests that the rotenone content is not necessarily a Toll- 
able index to the toxic value of derris root. Rotenone, doguelin, and 
toxicarol vrere only moderately toxic to the insects. The aquoous solutions 
of derris root or crushed freshly harvested roots vrere toxic to the larvae 
without actual contact, indicating that dorr is may yield a volatile toxic 
substance. Fluids obtained from derris by steam distillation vrere also 
toxic to larvae of the same 2 species when immersed therein, killing 19 per- 
cent of S_. pecten . The indications were that derris may affect the nervous 
system of insects through the integument and ncy clso act as a repellent. 
