459 



packed soil. After emergence they oviposit on the young plants. A 

 general average of 10,000 stalks examined showed greater infestation 

 in the plant cane than in the stubble. Owing to the difficulty in obtain- 

 ing seed cane free from borers, experiments are being conducted at 

 Audubon Park, Louisiana, with a view to killing the borers in the cane ; 

 in this connection paradichlorobenzene has so far given promising 

 results. Another suggestion is that an area of about a mile square 

 be devoted to stubble cane and maize for a year. As the borers attack- 

 ing maize originate in the seed cane, the elimination of the latter should 

 tend to reduce the infestation. So far there has been no opportunity 

 of testing this method. 



/ Zacher (F.). Sudamerikanische Kakaoschadlinge. [South American 

 Cacao Pests.]— Dt'A- Tropenpflanzer, Berlin, xxv, no. 6, July- 

 August 1922, pp. 119-121. 



This brief review of the various insect pests of cacao in South 

 America is compiled from pubhshed sources. 



Rankin (W. H.) & Hockey (J. F.). Mosaic and Leaf Curl of the 

 Cultivated Red Raspberry.— Can «^f a Dept. Agric, Domin. Exptl. 

 Farms, Div. Bot., Ottawa, Circ. N.S. no. 1, March 1922, 3 pp. 

 [Received 10th July 1922.J 



The nature and symptoms of these diseases are described and the 

 susceptibiUty of different varieties of raspberries is discussed. Both 

 mosaic and leaf-curl are transmitted by Aphis ruhiphila, which spends 

 its whole life on the raspberry plant. Eggs are laid in the axils of the 

 buds on the suckers, and Aphids that hatch and feed on diseased canes 

 in the spring crawl to adjoining bushes with new green suckers in 

 search of better food, carrying with them the infection. 



Great care should be taken to plant only disease-free stock ; infes- 

 tation from neighbouring ground is not likely to occur, as the Aphids 

 do not apparently develop a winged state in the field and will not 

 therefore travel any distance. Diseased plants should be removed at 

 the time of year when the Aphids are not active. All plants affected 

 by leaf-curl should be dug up and carried to a distance from the 

 plantation as soon as the symptoms are distinguishable in the spring. 

 As this must be done before the Aphid eggs hatch, within a week or so 

 of 1st May is usually the best time. For mosaic disease the best time 

 for removal has not been definitely determined, but will probably be 

 the period immediately following the first two weeks of steady hot 

 weather in the summer. The diseased plants must be hfted away and 

 not dragged, as this would merely scatter the Aphids about the planta- 

 tion, the eradication of mosaic bushes must be finished before the 

 cooler weather of late summer, when the Aphids again become active 

 and more numerous. The selection or breeding of immune varieties is 

 a problem for the future. 



DowNES (W.). The Strawberry Root Weevil, with Notes on other 

 Insects affecting Strawberries.— Ca««rfa Dtpt. Agric, Ent. Branch, 

 Ottawa, Pamphlet N.S. no. 5, January 1922. 16 pp., 5 figs. 

 [Received nth July 1922.] 



A detailed account is given of the Hfe-history and control of 

 Otiorrhynchus ovatus, L. The latter consists mainly of cultural methods, 

 including ploughing of infested fields at the proper time of year and 



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