warm daj^s, however, hordes of small parasitic flies appear and in a 

 few days often completely rid the plants of aphids. 



Remedies. — Although these plant-lice may be readil})- destroyed by 

 spraying with kerosene emulsion, whale-oil soap, or tobacco water, as 

 the writer has demonstrated, yet it would hardly seem, judging from his 

 observations, that the use of these insecticides will as a rule be profit- 

 able in this particular case. Fall and winter plowing which will keep 

 the fields clear of weeds during the winter will undoubtedly have a 



Fig. 2.— Aphis gossypii: a, winged female; aa, enlarged antenna of same; ab, dark female, side view; 

 b, young nymph or larva; c, last stage of nymph; d, wingless female— all greatly enlarged (after 

 Chittenden). 



beneficial eft'ect in reducing the numbers of plant-lice, and in some cases 

 will be the only treatment necessary. 



THE GARDEN WEBWORM. 



The so-called "web worms'' or "careless worms" {Loscostege simi- 

 lalis Guen.) often destroy 3'Oung cotton and corn over considerable 

 areas, as was especially the case in northern Texas and in Oklahoma in 

 1908. The name "careless worm" is derived from the normal food 

 plant of the species, the "careless weed" (Amaranthus), upon which 

 these webworms always feed by preference. It is in fields grown up 

 to these weeds that the caterpillars are always worst, and if these are 

 kept down the insects will be much less troublesome. 



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