Entomological Notes. 285 



The next day all were again examined with great care, so that 

 very few, if any larva?, were omitted in the count. 



Number one, cabbages, 9; larva dead, 17; stupefied, 39; alive, 3. 

 Number two, cabbages, 10; larva dead, 42; stupefied, 30; alive 1. 

 Number tbree, cabbages, 26; larva dead, 18; stupefied, 0; alive, 58. 

 Number four, cabbages, 13; larva dead, 25; stupefied, 3; alive, 1. 

 Number five, cabbages, 20; larva dead, 18; stupefied, 3; alive, 9. 

 Number six, cabbages, 20; larva dead, 9; stupefied, 0; alive, 1. 



Feiday, October 1, 1880. 



First experiment — Treated twelve cabbages ; used one gallon 

 of water and one-half spoonful of Pyrethrum. Careful exami- 

 nation revealed eleven dead and eleven alive. 



Second experiment — Twelve cabbages ; used one gallon of 

 water to one-fourth spoonful (two grammes) of the powder. 

 Eleven dead and four alive. 



Third experiment — Twenty-six cabbages; used Pyrethrum 

 and flour, one to forty. Three dead, five alive, and one stupefied. 



Fourth experiment — Twelve cabbages; one gallon water to 

 one spoonful of the powder. Result, thirteen dead, four alive 

 and four stupefied. 



The above experiments show conclusively that this powder is 

 fatal to the caterpillars, and that, too, in very dilute liquid mix- 

 tures, as only one two-hundredths of a pound to the gallon of 

 water was used in experiment two of October 1st, and eleven 

 larva? were killed. We have only to sprinkle it on the plants, 

 though it may be necessary to make more than one application to 

 insure complete success. The success was better with the liquid 

 than with the flour mixture, and can be applied with greater 

 speed and economy. 



A twig of alder (Alnus serrulata), covered beneath with woolly 

 Aphides (Eriosoma tesselatum, Fitch), was dipped into the liquid 

 mixture of one-fiftieth of a pound to a gallon of water. The 

 next morning all the lice had fallen to the ground, never to rise 

 again. 



Flies and mosquitoes in a room where the powdered Pyrethrum 

 had been blown in not very large quantities, less than one one- 

 hundredth of a pound to a room twelve feet square, were felled 



