69 



small numbers are to be found in Victoria, Okanagan Landing, West- 

 bank and Kaleden, while at Vancouver and Kelowna it would probably 

 be found on careful search. During the past six years, fruit crops 

 Jiave greatly increased and varying and, increasing numbers of codling 

 moth outbreaks have occurred, xis a whole, however, the main fruit 

 areas are not yet affected. 



Davis (M. B.). A Test of diflerent Arsenates of Lead. — Rept. Div. 

 Hoitic. for the Year ending March 31, 1915, De])t. Agric. Ottaiva, 

 pp. 616-617. [Received 5th December 1916.] 



Twelve brands of commercial arsenate of lead, both in the powdered 

 and in the dry form, were tested as to adhesive qualities and injurious 

 effect upon foliage. They were also tested by the Chemical Division, 

 with the result that from the two sets of data it is shown that one 

 preparation costing considerably more than another is often the cheaper 

 on account of its greater percentage of arsenic. The percentage of 

 soluble arsenic was never as great as 1 per cent, and no scorching of 

 foliage resulted, though the insecticide was applied at the rate of 

 10 lb. to 40 gals, of water. The powdered form appeared to mix better 

 with water than the paste and had a higher adhesive value, owdng to 

 the particles being more finely divided. 



Purchasers of commercial arsenates of lead should ascertain from the 

 retailer or manufacturer the percentage of arsenic oxide and purchase 

 on the unit basis. Assuming that a certain paste contains 14-35 per 

 cent, of arsenic oxide and a dry preparation 32 '18 per cent, of the oxide, 

 and that the latter costs £4 per 100 lb. and the former £2 155., in the 

 case of the dry preparation the cost is about 2s. M. for each per cent, of 

 oxide as compared with 2>s. in the case of the paste. There is also a 

 saving in carriage. 



Gibson (A.). The Control of Ants in Dwellings. — Canadian Entomo- 

 logist, London, Ont., xlviii, no. 11, November 1916, pp. 365-366. 



The common carpenter ant, Camponofus pennsylvanicus, was found 

 to be controlled by dusting sodium fluoride powder into the openings 

 between the beams and roof and other cracks or openings by means of a 

 puffer or dust gun in the evening. The same experiment was tried in 

 another locality against the common shed-builder ant, Cremastogaster 

 lineolata, with equal success. In every case one ajjplication of the 

 powder was found sufficient. 



Hoss (W. A.). The Susceptibility of the Eggs of Aphis pomi and 

 Aphis avenae to Hydrocyanic Acid Gas. — Canadian Entomologist, 

 London, Ont., xlviii, no. 11, November 1916, p. 367. 



It is noted that the fumigation of young apple trees with hydro- 

 cyanic acid gas just before or shortly after the buds commence to 

 swell not only controls the San Jose scale [Aspidiotus perniciosiis], but 

 also destroys the eggs of Aphids. Of seven trees well stocked with 

 the eggs of Aphis ])omi and Aphis avenae, three were fumigated with 

 hydrocyanic acid gas (1 oz. KCN to 100 cubic feet, 1 : 13 formula) for 

 forty-five minutes. None of the eggs on the fumigated stock hatched, 

 whereas large numbers did so on the control trees. 



