THE CANADIAN ENTOMOLOGIST. 47 



Another arsenical compound was also tested, known in commerce as 

 Powdered Cobalt, or Fly-Poison. This was used in the same proportions 

 as the last-mentioned, and with similar results, but owing to its higher 

 price we do not recommend it for general use. 



Sulphate of Copper (Blue Stone). — A strong solution of this salt 

 was tried in the proportion of two ounces to one gallon of water, and 

 showered on the vines with a watering pot, without damage to either the 

 insect or the plant. 



Bichromate of Potash. — This is a poisonous substance, largely used 

 in dyeing, and one which has attracted some attention in France of late, as 

 a remedy for insects. We used it dissolved in water in the proportion of 

 two ounces to three gallons of water. This killed the insects effectually, 

 but, at the same time, destroyed the plants. Whether, in a more diluted 

 form, this remedy could be effectively used without injury to the foliage, 

 we are unable at present to say, but shall experiment further with it. 



Powdered Hellffjore.-- This powerful irritant, which is so effectual 

 as a remedy for the Currant Worm, we tried without perceptible effect, 

 both in powder and also mixed with water. Several other poisonous 

 substances were also used with like results. 



Carbolate of Lime. — There are several preparations sold under this 

 name, which we found to vary much in composition and character, and 

 equally so in effect. We tried an article known as Dougall's, without any 

 good result, but succeeded better with one prepared by Lyman Bros, of 

 Toronto, a black powder manufactured, we understand, from coal tar. — 

 This destroyed a large proportion of the larvae, but we doubt whether it 

 would kill the perfect insect ; it is, moreover, used in an undiluted form, 

 which would render its cost greater than that of the Paris Green mixture, 

 so we see no advantage in using it, although the fact of its being less 

 poisonous may induce some to try it who are prejudiced against Paris 

 Green. 



Ashes and Air-slacked Lime, we found, had been extensively used 

 by many of the formers on the frontier districts, but, as far as we could 

 see or learn, without any perceptible results. 



hand-pickino. 



This has been, thus far, the chief means employed in lessening the 

 numbers of the beetle, and, where perseveringly followed, has proved 



