374 



trees were attacked very exceptionally, and this applies to the grape 

 vine, either in cultivation or allowed to run wild. vStrangely enough 

 such immunity extended to standing corn, though the chaff on threshing 

 floors was eagerly sought for by the adults, which are also attracted 

 to places where lentils, vetches, etc., are being threshed. 



The lack of natural enemies was one reason for the outbreak. The 

 beetle, Mylabris [Zonabris) variabilis, seems to be of little value, even 

 if it were not so rare. 



The government supplied insecticides and poisons for the campaign, 

 which was carried out b}^ land-owners and local authorities. Du'ect 

 spraying of the locusts, the spraying of the grasses, and the use of 

 poison-bran baits were resorted to. Lead arsenate, zinc phosphide, 

 cresosol emulsion, and sodium arsenite were employed. Cresosol gave 

 good results, but should only be used when sodium arsenite is not 

 available ; it scorches vegetation, injures rubber tubing, and costs 

 more than the arsenite. Lead arsenite scorches vegetation if used in 

 the large doses necessary to kill locusts, and is quite the most expensive 

 poison in use. Sodium arsenite was the best material, and only half 

 the quantity was needed as compared with zinc phosphide. If it 

 becomes possible to reduce the phosphide to an exceedingly fine dust, 

 it may compare with the arsenite, over which it has the advantage 

 of not scorching. On the whole, the campaign was satisfactory, but 

 the need for a regulation compelhng careless land-owners to apply 

 the measures was felt. 



Malenotti (E.). Le Cavallette [Calliptamus t7a/icMs— Grillastro 

 italiano). Istruzioni pratiche per distruggerle mediante I'Arsenito 

 di Sodio. [Locusts (C. italicus). Practical Instructions for 

 destroying them with Sodium Arsenite.] — Minist. Agric. Direzione 

 Gen. Agric, Verona, November 1921, 4 pp. [Received 16th 

 May 1922. J 



The preparation and appHcation of a solution containing 1 • 5-2 per 

 cent, of sodium arsenite as a spray against locusts, Callipiamiis italicus, 

 are described. Many of the disadvantages attaching to this method 

 disappear if a weaker solution (1 per cent.) is used to spray the herbage 

 instead of the insects. Danger to cattle and all risk of scorching plants 

 can be avoided by using a poison-bran bait containing from 3 to 4 per 

 cent, of the poison according to the age of the locusts. 



Bernard (C). Verslag van het Algemeen Proef station voor Thee 



over het Jaar 1921. [Report of the General Tea Experiment 

 Station for 1921.] — Meded. Procfst. voor Thee, Buitenzorg, no. 78, 

 1922, 32 pp. [Received 16th May 1922.] 



Some of the matter contained in this report has already been noticed 

 [R.A.E., A, ix, 493; x, 175, 176, 281]. In Java, Helopeliis was the most 

 serious pest of tea. Brevipalpiis obovatiis and Tarsonemiis Iranslucens 

 occurred to some extent, while other mites noticed were TetranycJins 

 biocidatiis, Eriophyes {Phytoptus) theae and E. (P.) carinatus. These mites 

 decreased at the beginning of the rainy season . Tetranychus bimamlatus 

 occurred on cinchona. The caterpillars of Setora nitens and Andraca 

 hipiinctata (bunch caterpillar) caused some serious injury to tea. 

 Heliothrips haenwrrhoidalis badly damaged the leaves in some seed 

 plots. Pests of little importance included the tea seed -bug 

 {Poecilocoris) , Coccids and Aphids. 



