65 



FuLMEK (L.). Zur Kenntnis der Raupe und Puppe von Buccnlatrix 

 thoracella, Thbg. [A Contribution to the Knowledge of the 

 Caterpillar and Pupa of B. thoracella.'] — Zeitschr. angew. Entom., 

 Berlin, vi, no. 2, February 1920, pp. 330-337, 11 figs. [Received 

 2nd December 1920.] 

 The larval and pupal stages of Bucculatrix thoracella, Thbg., are 



described. The cocoons, some of which were parasitised by Chalcids, 



were observed on lime-trees in Vienna. 



Andres (A.) &Muller (A.). Ein einfaches Verfahren der Blausaure- 

 entwicklung aus Cyannatriumlosungen und seine Verwendung zur 

 Bekampfung schadlicher Insekten. [A simple Process for 

 generating Hydrocyanic Acid Gas from Solutions of Sodium 

 Cyanide and its Use for combating injurious Insects.] — Zeitschr. 

 angew. Entom., Berlin, vi, no. 2, February 1920, pp. 372-389. 

 [Received 2nd December 1920.] 

 Hydrocyanic acid gas is generated when a solution of sodium 

 cyanide is poured on the soil. No importance has hitherto been 

 attached to this fact, which may be of value in combating insect pests. 

 Warm, dry ground favours the generation of the gas. . The composition 

 of the soil is an important factor, sand being less suitable, though the 

 addition of ammonium sulphate will help the production of gas in this 

 medium. Sodium cyanide is dangerous to plants if it comes in contact 

 with their roots, but the decomposition product (soda) is harmless. 

 It is therefore dangerous to adopt this method on ground in which 

 plants are already growing, though no harm will result if the soil is 

 treated some days prior to planting. In order to confine the gas, 

 it is necessary to cover the ground, immediately after treatment, 

 with some material such as newspaper, balloon silk, or packing paper, 

 the edges of the covering being weighted. The ground must be kept 

 covered for at least 45 minutes. Flea-beetles and Aphids may be 

 killed in this manner. The ground must be dry and have a minimum 

 temperature of 65° F. (18° C.). It is necessary to use 2^ htres of a 

 5 per mille solution of sodium cyanide per square metre (about 4| pints 

 per lOf sq. ft.). This strength does not injure either savoy or white 

 cabbage if treatment is carried out in the evening. In hot-beds, pot- 

 plants infested with Aphids and Coccids may be treated in the same 

 manner. 



Hase (A.). Ueberdie erste deutsche Forstentomologische Feldstation. 



[Notes on the first German Field-station for Forest Entomology.] 

 — Zeitschr. angeiv. Entom., Berlin, vi, no. 2, February 1920, 

 pp. 390^00, 6 figs. [Received 2nd December 1920.] 



Owing to the present financial conditions in Germany it is doubtful 

 whether funds will be available for entomological field stations. 

 Economic entomologists must attract pubhc notice to the need for such 

 stations and must endeavour to secure financial assistance from sources 

 other than the State. 



Owing to the action of the municipal authorities of the town of 

 Guben, the first German field station, or rather, forest station, has 

 been estabhshed in a forest of about 12,000 acres chiefly planted with 

 pines, some of which are infested with Dendrolimus {Gastropacha) pint. 

 Investigations are to be conducted on this moth and on methods for 

 combating it. 



