564 



the temperature of the entire hand is not raised. Hot water acts 

 instantaneously and for a very brief period of time ; the action of 

 hot, damp air is much slower. 



Ravaz (L.). Encore I'eau chaude. [Hot water again.] — Progres Agric. 

 Vitic, Montpellier, Ixiii (32nd vear), no. 24, 13th June 1915, 

 pp. 555-558. 



M. Faes, Director of the Vine Research Station at Lausanne, has 

 communicated detailed information regarding experiments with hot 

 solutions undertaken in 1903. At temperatures between 113° and 

 122° F., their insecticidal power was certainly enhanced. Hot water 

 alone was insufficient when under 122° F. Vines did not appear to be 

 affected by solutions between 104° and 122° F. 



The author is doubtful whether hot solutions may iiot decompose 

 or rapidly deposit the cupric salts which are the active ingredient in 

 the sprays. Not only is the precipitate more rapidly thrown down 

 in a hot solution, but it occupies a smaller volume, owing to the fact 

 that heat agglomerates a precipitate. A dense precipitate is less 

 easily acted on by dissolving agents, such as atmospheric carbonic 

 acid, than a fiocculent one. In making up spray mixtures, vine- 

 growers have always aimed at obtaining a well-diifused precipitate. 

 A further disadvantage of the hot method is that heat transforms 

 certain bodies sensitive to the dissolving action of the carbonic acid 

 contained in water into almost inactive compounds ; thus, the blue 

 hydrocarbon ate of copper, found in nearly all spray solutions, is 

 rapidly changed by heat into a malachite green, dense hydrocarbonate, 

 which is but slightly dissolved by carbonic acid. Hot water does not 

 therefore enhance the quality of a cupric spray. In any case, the 

 whole matter is far from being decided. 



Scott (H.). Swarm of Baryjnthes (Exomias) pelliicidus, Boh., in 

 Cambridgeshire, and notes on its iood-plants.^Entomohgists^ 

 Mthhj. Mag., London, no. 614, July 1915, pp. 218-219. 



A swarm of these weevils occurred in May 1915, at Fordham ; kale, 

 kohl-rabi, peony-flowered poppy, Nemophila insignis, Collinsia 

 bicolor and Acer marginata aurea were attacked. Gypsophila elegans, 

 potatoes, peas and spruce escaped injury. The weevils generally 

 feed on the lower surfaces of the leaves. Many seedlings were eaten 

 •off just above the ground. The infested plants were treated with a 

 mixture of lime and soot, which proved effective. 



Hewitt (C. G.). The Outbreak of the Western Army Cutworm in 

 Southern Alberta. — Agric. Gaz. Canada, Ottawa, ii, no. 6, June 

 1915, p. 521. 



During 1914, the moths of the western army cutworm, Euxoa 

 {Chorizagrotis) agrestis, were extremely abundant in Southern Alberta, 

 and a serious outbreak was expected and occurred in the spring 

 of 1915. The value of early trenching was demonstrated. Deep 

 furrows were ploughed round infested fields, after which a log, with a 



