104 



sticky shields. Pruning and the use of insecticides are not recom- 

 mended, as any sprays strong enough to kill the bugs would injure 

 the plants. 



DE LA Barreda (L.). Un Hemiptero en los Pinos. [A Hemipteron 

 on Pines.] — Rev. Agric, Mexico, D.F., ii, no. 9, 1st July 1918, 

 pp. 376-378, 2 figs. [Received 29th December 1921.] 



Pines in the forest of Chapultepec are infested by an unidentified 

 Aphid. The first sign of injury is the withering of the needles ; this 

 is followed by that of the terminal branches, and finally the tree dies. 

 Experiments with various insecticides showed that the best remedy 

 was spraying with a 1 per cent, solution of alcohol in water, repeated 

 every eight days until the cottony secretion that reveals the presence 

 of the insect no longer reappears. 



DE LA Barreda (L.). El Cascalote atacado por dos Bruchus. [Caesal- 

 pinia coriaria attacked by two Bruchids.] — Rev. Agric, Mexico, 

 D.F., iv, no. 5-6, 1st May 1919, pp. 256-259, 1 plate. [Received 

 29th December 1921.] 



In June 1918 stored pods and seeds of Caesalpinia coriaria, which 

 are used in tanning, were badly infested by two species of Bruchid 

 beetles. Fumigation with carbon bisulphide at the rate of 40 grammes 

 per cubic metre of space is the remedy advised The treatment may 

 be prolonged up to 48 hours without damage. 



Madariaga (A.). Plagas y Enfermedades del Maiz. [Pests and 

 Diseases of Maize.] — Rev. Agric, Mexico, D.F., iv, no. 9-10, 1st 

 July 1919, pp. 449-455. [Received 29th December 1921.] 



The pests of maize in Mexico include : Tetranychus himaculatus and 

 other mites ; Aphis maidis ; Heliothis obsoleta, which has 3-5 genera- 

 tions a year ; Diatraea saccharalis ; Macrodactyliis mexicanns and 

 M. silaonus ; Diahrotica longicornis ; Lachnosterna spp., the larval 

 stage of which may last three years ; and grasshoppers and locusts 

 belonging to the genera Melanoplus, Bracliystola and Schistocerca. 

 The measures advocated against these are those commonly, employed. 



Stored maize is attacked by various Lepidoptera, including Sitotroga 

 {Gelechia) cerealella, and by several beetles, especially weevils of the 

 genus Calandra. Fumigation with carbon bisulphide is recommended 

 against these. 



CooLEY (R. A.). Late Developments in Arsenical Insecticides. — 



Better Fruit, xv, 1920, no. 5, pp. 9, 10, 16. (Abstract in Expt. 

 Sta. Record, Washington, D.C., xlv, no. 5, October 1921, p. 455.) 

 [Received 4th January 1922.] 



Crude white arsenic obtained from Montana smelters at a low cost 

 has given quite satisfactory results when used in grasshopper control. 

 It was also found that it could be used as a spray on potatoes for the 

 control of the potato beetle [Leptinotarsa decemlineata] without injuring 

 the foliage, a result perhaps due in part to the short period of time 

 that the arsenic was in the water, since, when sprayed on the plants, 

 the water evaporated very quickly. The first experiment was with 

 the refined white arsenic, and later the crude product was applied as a 

 dust, with even better results, probably owing to its fineness. 



