520 



JOURNAL OF ECONOMIC ENTOMOLOGY 



[Vol. 8- 



On the ^'Island Farms" at Alameda the work of the larvse upon 

 the roots of the cucumber plants was identical with that of the striped 

 cucumber beetle (Diabrotica vittata Fab.) in Minnesota. 



The adults are not usually of sufficient importance to demand reme- 

 dial measures, but the larvae will destroy a patch of cucumbers in a 

 very short time. Eggs are deposited about two inches below the 

 surface of the soil on the tap root of the plant. When they hatch the 

 young larvae begin working upwards on the root-stalk and appear above 

 the ground in two or three days. Soon the flat sides of the stalk near 

 the corners begin to turn white and the leaves nearest the roots show 

 a white border; then the whole plant begins to wither, the small cucum- 

 bers curl and assume awkward shapes, and, if the insect cohti^ues, the 

 plant dies. 



Tobacco extract, nicotine, is a successful remedy. Various forms 

 of this extract may be had at the drug store, at about two dollars per 

 pound for 40 per cent solution. Counting one teaspoonful of the 

 solution to a gallon of water, a pound can will be sufficient to treat 

 one thousand hills and a man can treat fourteen hundred hills a day. 



When the larvae appear on the stalk, just above the surface of the- 

 soil, take a narrow half pint cup and pour the solution carefully against 

 all sides of the stalk in such a manner that it will run down. The- 

 solution will kill the larvae without touching them, but the burrows in 

 the stalk may be very deep — the larvae will finally work to the pith — • 

 in which case a quick splash of the liquid into the burrow would be 

 most likely to kill the insect. Everything depends upon the way in 

 which the liquid is applied. Care and judgment are equally demanded.. 

 A good way is to squat down with the cup of liquid in one hand while 

 keeping the other hand free to carefully move the plant that there 

 may be no guess work about where the insect is working and that the 

 liquid may be poured in the right place. 



Department of Entomology, University of California, 

 Berkeley, Cal., August 30, 1915. 



LEPTINOTARSA DECEMLINEATA SAY 



By W. O. Ellis 



During the summer of 1913, while acting as an assistant in the Ento- 

 mological Division of the Iowa x\gricultural Experiment Station, the 

 following record on oviposition was obtained: 



From a female captured July 7 and placed in confinement with a. 

 male, the writer obtained a total of 1,686 eggs. The experiment con- 

 tinued to September 1, or a period of fifty-five days. On July 28 the 



