-32* - 
Brotoloinia meticulos a ( L . ) 
This pest on roses was killed by a product containing 12 percent of 
powdered Lonchocarpus nicou root ( 6 percent rotenone content) and 88 per- 
cent of talcum, according to Etablissements P.otenia in 1938, in a letter to 
R. C. Roark. 
The Experimental and Research Station, Che shunt, England ( 115 ), in 
1939 stated that derris dust prevented the feeding of caterpillars of the 
angle-shades moth. 
Busseola fusca (Fuller) 
Ripley ( 349 ) in 1926 reported results of tests with proprietary derris 
products against the maize stalk borer in South Africa. Kymac at 1:300 
burned the plants and did not control the borer; it was recommended that, 
to avoid burning the young maize, Derrisol be used at 1:150, the highest 
concentration practicable for large-scale use. In 1927 this author ( 350 ) 
reported that a case of delayed plant poisoning- had followed the use of 
Derrisol, but that this did not occur in the Cedara experimental plots, 
even when Derrisol was used at much stronger concentrations than those 
recommended for trial. For other purposes Derrisol v/as found to be an ex- 
cellent insecticide. The Union of South Africa Department of Agriculture 
( 424 ) in 1927 referred to work by Ripley against the stalkborer and stated 
that the sheep dip Kymac at 1:200 proved safe for top-dressing young maize 
plants. In 1928 Ripley ( 351 ) reported that Kymac at 1:250 is a safe top 
-dressing for maize if used at the rate cf 10 cc. of liquid per plant. At 
1:100, Kymac caused severe burning and reduced the yield 25 to 38 percent, 
Ripley and Hepburn (352) in 1928 reported that a water suspension of 
powdered derris root (1:90) was much more effective than dry powder (1:12) 
as top-dressing against this insect. Pulvox (ground derris root) at 1:450 
by weight, and Kymac (sheep dip containing derris extract) at 1:250 are 
about equal in effectiveness and in cost. Pv.lvex does not injure maize 
foliage but, according to these authors (353) in 1929, Kymac at concen- 
trations greater than 1:250 burns maize foliage. It was concluded that 
Pulvex in water 1:450 by weight v/as the most suitable of the derris products 
studied. The same authors ( 354 ) in 1930 reported that Pulvex, 1 pound to 
40 imperial gallons of water used as a top-dressing against the insect, 
increased the corn yield 13 percent and v/as harmless to the foliage; Kymac, 
1 pound to 25 imperial gallons, gavo an increase of 27 percent in yield 
but injured the foliage. Derrisol, 1 part tc 1,000 parts of water by 
measure, was recommended. Preliminary experiments with a Derrisol-cryolitc 
mixture gave promising results. 
Pulvox has been tried, but in 1930 Ripley and Hepburn (354) found that 
Derrisol gave bettor results. It does not harm the plants, even in exces- 
sive strength and has superior penetration and adhesion. Derrisol should 
be diluted 1:1,000 in water and about 1 dessert spoonful of the liquid put 
into the crown or top of the maize plant. The correct 'cime to make the 
first application is when a small percentage of plants show pt ed 
inner leaves and about 33 percent show mottled leaves. 0) lion of 
Derrisol is sufficient to top-dress 45 acres of maize and one native 
top-dress from 1 to 3 acres per day. These authors (_ i 1934 reported 
