754 EXPERIMENT STATION EECOED. 



pp. 27-42; abs. in Zhur. Opuitn. Agron. [Buss. Jour. Expt. Landw.l, 10 (1909), 

 Xo. 1, pp. 82, 83). — This article is a critical review of the existing measures for 

 combating injurious insects. 



Plant pest treatment, H. A. Surface (Zool. Bui. Penn. Dept. Agr., 7 {1909), 

 No. 1, pp. 31). — In Section A a list is given of the plants or property liable to 

 injury, with references to Section B in which are given formulas and methods, 

 and to Section C in which directions are given as to the dates and periods of 

 application. 



The use of iron arsenate as an insecticide, V. Vermoeel and E. Dantony 

 [Compt. Rend. Acad. 8ci. [Paris], l.',8 {1909), No. 5, pp. 302-30 4) .^The authors 

 have conducted experiments with iron arsenate and here report upon its value 

 as an insecticide. Considerable success has followed its use during 1906, 1907, 

 and 1908 in combating the codling moth. 



It is prepared by slowly adding 400 gm. of iron sulphate dissolved in 10 

 liters of water to an equal amount of arsenate of soda also dissolved in 10 

 liters of water. The solution should be constantly agitated as the addition is 

 made. Due to the variation in the purity of these chemicals it is necessary 

 toward the end of the operation to test the mixture with potassium ferrocyanid 

 (or potassium ferricyanid) paper in oi'der to prevent an excess of the iron 

 sulphate. No more of the solution should be added after the paper turns blue 

 and it is also important that there should not be an excess of soluble arsenate. 



The stock mixture should be diluted with water to make 100 liters and will 

 contain 200 gm. of ferrous arsenate per hectoliter, also some sulphate of soda 

 and ferrous hydrate. When in contact with the air the ferrous arsenate turns 

 greenish, becoming ferroso-ferric arsenate, and the ferrous hydrate turns to 

 ferric hydrate, which is the best antidote for arsenic poisoning. The general 

 color of the spray material is a dirty green and can not be mistaken for any 

 food product. The maximum adhesive power is reached at the dilution here 

 given. 



Iron arsenate and the arsenical salts, V. Yermorel and E. Dantony {L'Ar- 

 seniate Ferreux et Ics Sels Arsenicaux. MontpelUer and Villefranche, 1909, 

 pp. 52). — This work discusses the arsenical insecticides, particular attention 

 being given to iron arsenate, a brief account of which is above noted. On the 

 basis of several years' experiments the authors conclude that the action of iron 

 arsenate, as an insecticide, is equal and sometimes superior to that of lead 

 arsenate. It is easily prepared for use and its adhesive power is greater than 

 that of similar products. 



Among the advantages that this insecticide has over lead arsenate are its 

 characteristic color which prevents a mistaken use and the presence of iron in 

 place of lead, the former having a beneficial effect upon the foliage. The most 

 important advantage, however, is the cheapness of the product due to the 

 cheapness of sulphate of iron as compared with acetate of lead. 



A new method for making arsenical spray, E. H. Twight {Better Fruit, i 

 {1909), No. Ji, pp. 24, 25). — This is an account of the use of iron arsenate as an 

 insecticide as above noted. 



The termites or white ants, K. Escherich (Die Termiten oder Weissen 

 Ameiscn. Lcipsic, 1909, pp. XII +198, pi. 1, figs. 51; rev. in 8ci. Prog. Ttoentieth 

 Cent., Jt {1909), No. 13, pp. 171, 172).— This is a summary of the life history 

 and bionomics of termites. 



Locust destruction, A. Kelly- {Natal Agr. Jour., 12 {1909), No. 6, pp. 77/7- 

 7-'/9). — This is a report of tlie work for the season of 190.S-!) in Natal. 



Combating the migratory locusts w^ith chemical products, J. Schroeder 

 {Ztschr. Pflanzenkrank., 19 {1909), No. 1, pp. 1-13, figs, h; Bui. Mens. Off. 



