406 



Zavitz (C. a.). Treatments for the Colorado Potato Beetle, DorypJiora 

 decemlineata. — Ontario Dept. Agric, Toronto, Ont. Agric. Coll. 

 Bull. no. 239 (Potatoes), May 1916, pp. 75-78. 



In experiments against Leptinotarsa (Doryphora) decemlineata, 

 twenty-one separate examinations were made of the number of beetles 

 per plant a few days after the first treatment in the season, as well as 

 of the percentage of fohage eaten a few days after the second and third 

 treatments. Eleven plots, each differently treated, were examined 

 on each occasion, the results of these examinations being given in a 

 table. The first figure represents the average number of beetles per 

 plant and the second figure the average percentage of fohage eaten. 

 Four preparations of Paris green and water (4 plots) gave 3'3 and 5"0 ; 

 three preparations of commercial lead arsenate (3 plots) gave 4'0 and 

 8'1 ; three preparations of home-made lead arsenate (3 plots) gave 

 10*7 and 33' 1 ; hand-picking (1 plot) gave 2'8 and 14"9. 



Childs (L.) Entomologicallnvestigations, 1915 : The Fruit-tree Leaf- 

 roller ; Codling Moth Investigations ; Woolly Aphis investigations 

 for 1916 ; Strawberry-root Weevil investigations for 1916. — Rept. 

 Hood River Branch Expt. Sta. for 1914-1915, Oregon Agric. Coll., 

 Corvallis, pp. 47-61, 2 figs. 



The data relating to the control of the fruit-tree leaf-roller [Cacoecia 

 argyrospila] in this paper have already been abstracted [see this 

 Review, Ser. A, iii, p. 758]. 



Against Cydia pomonella, the calyx and 30-day spray (the first two 

 apphcations) are advised in both cases for the control of the first brood 

 of caterpillars. Where a loss of not more than 8 per cent, was 

 experienced in 1915, one well-timed summer spray, early in August, 

 would be effective against the second generation. Where the infest- 

 ation was over 8 per cent, or 10 per cent., two summer applications 

 should be made, the first of these being made about 20th July and the 

 other towards the middle or end of August. 



Preliminary investigations on the woolly aphis [Eriosomalanigerum], 

 which has increased in the Hood River district in the last two years, 

 showed that the Aphids pass the winter, for the most part, as nymphs 

 or young insects. The following contact insecticide is recommended 

 against them : miscible oil, 4 to 5 U.S. gals. ; whale-oil soap, 2 to 

 3 lb. ; water, 100 gals. If C. argyrospila is present, the oil should be 

 increased to 6 U.S. gals. 



Preventive measures against the strawberry-root weevil [Otio- 

 rrhynchus ovatus] include the selection of plants from non-infested 

 districts and the destruction of the soil and packing around them. 

 These precautions will lessen the chance of infesting new areas. At 

 present there is no really satisfactory means of controlhng this 

 pest. 



QuAiNTANCE (A. L.). The Leaf Blister Mite of Pear and Apple.— 

 U.S. Dept. Agric, Washington, B.C., Farmers' Bull. no. 722, 

 21st April 1916, 6 pp., 4 figs. 



This paper deals briefly with the origin, distribution, habits, and 

 control of Eriophyes pyri, Pagst. (leaf blister mite of pear and apple). 

 Though the chief food-plants are pear and apple, this mite has also 



