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Itonididae (= Cecidomyidae ) 
"Cecidomia negri " 
According to the Etablissements Rote.nia in 1938, in a letter to 
R. C. Roark, "Cecidomia negri" [ Lestremia . nigra Blanchard may "be 
intended] on pear trees was mitigated by a product 'containing 12 per- 
cent of powdered Lonchocarpus nicou root (6 percent rotenone) and 
88 percent of talcum, 
Contarinia nasturtii Kief fer 
Leefmans ( 172 ) in 1938 reported that deformed heart of cabbage 
and cauliflower due to infestation by this species has caused con- 
siderable loss in northern Holland since it was first observed in 
1897. "The adults were found to bo sensitive, to derris and pyrethrum 
dusts. Headed cabbage must be sprayed twice a week, but in slight 
infestation of cauliflower one application weekly may suffice. Derris 
may be recommended as a dust insecticide, but spraying with a strong 
jet is more effective, as it tends to wash away both larvae and eggs. 
.Contarinia pyrivora (Riley) , the pear midge 
The University of Bristol Agricultural and Horticultural Research 
Station ( 59 ) in 1936 reported that field. trials to test the efficacy 
of a preblossom derris spray for control were defeated by the severe 
late frosts at two centers." At the third the results were not satis- 
factory. 
DeBussy et al. ( 48 ) in 1936 reported that the maggots are not 
affected by derris and results against the adults were unsatisfactory. 
Contarinia tritici (Kby.) 
Yuasa ( 528 ) in 1936 reported that sprays containing either nicotine 
sulfate or derris were effective for control of the wheat midge. 
Muhlow and Sjoberg ( 208 3 in 1937 reported on control of the wheat 
gall midges. No reduction in infestation was observed when plots 
were dusted heavily with 'pyrethrum powder or derris or sprayed with a 
solution, of rotenone. 
Dasynura mali Kief fer 
The Massachusetts Agricultural Experiment Station ( 199 ) in 1937 
reported that for control of the leaf-curling midge on apple derris 
extract, summer-oil emulsion, and lime-sulfur were about equally 
efficient in reducing the number of curled leaves and were more ef- 
fective than nicotine sulfate and a combination of soluble and in- 
soluble nicotine. Throe and four applications were generally more 
effective than one or two treatments, and this is significant because 
