19 



Stellwaag (F). Fruhjahrsbekampfung einiger wichtiger tierischer 

 Schadlinge der Obstbaume und Beerenstraucher. [Spring Treat- 

 ment against some important Animal Pests of Fruit Trees and 

 Bushes.] — Fhtgschr. d. staatl. Lehr- u. Versuchsanst. f. Wein- u. 

 Obsthau in Neustadt a.d. H., 1921, 2 pp. (Abstract in Centralbl. 

 Bakt. Paras. Infekt., Jena, lite Abt., liv, no. 20-24, 7th October 

 1921, p. 553.) 



Aphicls should be sprayed from below with nicotine. Against the 

 larvae of Nygmia phaeorrhoea and Malacosoma neiistria sprays of 

 Zabulon or Urania green must be used ; these sprays are also useful 

 ■against those of Cheimatohia hrumata when still on the trees. Urania 

 green is effective against Cydia pomonella ; spraying should be done, 

 preferably from above, immediately the petals fall. The larvae of 

 Pteromis ribesii should be sprayed with nicotine and soft soap, Zabulon 

 ■or Urania green, but the last-named must not be used when the fruit 

 is nearly ripe. 



ViDAi. (J. T.). Los Parasites de los Vegetales. [The Enemies of 

 Plants.] — Gaceta Rural, Buenos Aires, xiv, no. 167, June 1921, 

 pp. 1291-1295. [Received 7th November 1921.] 



It is probable that in future the work of combating diseases of 

 plants will primarily consist in the production and cultivation of 

 resistant varieties and in correct cultural procedure. 



While these methods may be of great value against insect pests, it is 

 probable that there will be a great development in the use of their 

 natural enemies. Insecticides, so largely employed at present, are 

 very costly, sometimes difficult to apply, and often merelv palliative 

 in effect. A number of cases are instanced in which insect pests 

 have been controlled by means of natural enemies. 



(i) Georgia Law to Regulate the Registration, Branding, Inspection 

 and Analyses of Insecticides and Fungicides, (ii) Insecticide and 

 Fungicide Standards adopted by the Georgia State Board of 

 Entomology, (iii) Ruhng of the Commissioner of Agriculture on 

 Tagging Packages of Insecticides and Fungicides. — Georgia State 

 Bd. Ent., Atlanta, Circ. 32, January 1921, 9 pp. [Received 

 7th November 1921.] 



The texts of these Acts, adopted 22nd October and 17th and 21st 

 November 1920, respectively, the provisions of which are indicated 

 in the title, are given verbatim. The standards for various insecticides 

 and fungicides adopted are as follows : — For calcium arsenate, not less 

 than 40 per cent, arsenic pentoxide and not more than 0-75 per cent, 

 water-soluble arsenic pentoxide ; density not less than 80 or more 

 than 100 cu. in. per lb. For lead arsenate paste, not less than 

 12-5 per cent, arsenic pentoxide, not more than 0-75 per cent, water- 

 soluble arsenic pentoxide, and not more than 50 per cent, water. 

 If extra water be added, the mixture must be labelled lead arsenate 

 and water, the percentage of extra water being plainly and correctly 

 stated on the label. For dry powdered lead arsenate, not less than 

 25 per cent, arsenic pentoxide and not more than 1 -5 per cent, water- 

 soluble arsenic pentoxide. For dust mixtures of sulphur or lead 

 arsenate and lime or other filler, not less than 10 per cent, pure sulphur, 

 or not less than 5 per cent, pure dry lead arsenate. Not less than 90 per 

 -cent, of the mixture must be fine enough to pass through a wire screen 



(5155) b2 



