221 



will also protect the crop from the fungi, Venturia spp. These mix- 

 tures are of two sorts, according to whether the anticryptogamic 

 substance is a copper compound or a polysulphide. Among the 

 copper-arsenical mixtures, Verdet lead arsenate is the most easily 

 prepared, but is apt to produce serious scorching. The author places 

 more confidence in Bordeaux arsenical sprays, which can be replaced 

 by polysulphide mixtures for application on the forming fruit. In 

 Bordeaux mixture, calcium arsenate is less expensive than lead arsenate 

 but seems rather less effective. The author recommends for preference 

 Bordeaux mixture made with 8 lb. copper sulphate with 40 lb. freshly- 

 slaked lime (or 20 lb. fat lime) per 10 gals, of water, to which is added 

 5 lb. lead arsenate previously mixed with part of the water. An 

 advantage will probably accrue in the future, in regard to the cost, 

 by the substitution of polysulphides for copper. These unite 

 readily with calcium arsenate, with the addition of a good quantity 

 of lime. Alkahne polysulphides cannot be used with lead arsenate, 

 but with lime-sulphur mixtures they form a very successful spray 

 which causes but little scorching. It is not likely, however, that these 

 lime-sulphur mixtures will readily become popular in France, owing 

 to difficulties attending their manufacture and to the established 

 custom of copper treatments. 



Section d'Entomologie, Apiculture, Pisciculture et Sericiculture.— 



Bull. Soc. Agric. France, Paris, hv, no. 2, February 1922, 

 pp. 48-49. 



White grubs have been very injurious to beets, especially in the 

 neighbourhood of Paris. Collection of the adult beetles has been 

 successfully practised in certain localities, no other remedial measure 

 practicable on large areas having yet been found. The root Aphid, 

 Trama troglodytes, Heyd. [Rhizohius radicis, Koch), has been fre- 

 quently observed on the roots of various salad crops. Much damage 

 was done to cabbage by the weevil, Ceuthorrhynchus assimilis, Payk. 

 The roots of cabbages should be pulled up and destroyed immediately 

 the plants have been cut, as they contain many larvae. The same 

 treatment should be applied to asparagus infested by the asparagus 

 fly, Platyparea poeciloptera, Schr. It is reported that the parasites 

 of the brown-tail moth, Nygmia phaeorrhoea, Don., have become so 

 well established in some districts as to destroy the moth in great 

 measure. 



Marie (P.). Application des Traitements Insecticides d'Hiver et 

 Destruction des Cochenilles. — Bull. Soc. Agric. France, Paris, 

 liv, no. 2, February 1922, pp. 37-40, 4 figs. 



Fruit trees in France, especially those in tLe smaller and more 

 neglected orchards, are often severely attacked by Coccids. The 

 importance of winter treatments with milk of lime or an alkaline 

 wash is emphasised, formulae being given for suitable washes. When 

 the bark is in good condition, one application towards the end of the 

 winter should be sufficient, but if the bark is old and cracked it should 

 be well scraped before the wash is applied ; all the old debris of the 

 bark should be collected in a cloth spread for the purpose, as it will 

 contain many young scales or eggs. 



