404 



with Paris green and barium chloride as a means of actually controlling 

 the pest ; but it was necessary to use a 6 per cent, solution of the latter 

 and to apply Paris green in the proportion of 4 lb. of green and 8 lb. of 

 lime in 55 gallons of water, to obtain more or less successful results. 

 The weaker solutions, usually recommended in entomological 

 literature, did not prove effective. These insecticides, at the above 

 strengths, produced a maximum death-rate of 23-24 per cent., but it 

 did not appear practicable to increase the strength, as no better results 

 could be obtained, while more concentrated insecticides affected the 

 leaves of beets. Experiments further showed that azurgin gave a 

 death-rate of from 4 to 12 per cent. , kerosene emulsion about 16 per cent. , 

 carbolic emulsion about 13 per cent., and tobacco extract, even at a 

 strength of 20 lb. of tobacco in 27 gallons of water, only 3 per cent. 

 Rolling did not harm the caterpillars, but damaged the plants ; hand 

 collection, although effective, proved expensive and better results, 

 were obtained by drawing between the beds drag-nets made of sail- 

 cloth smeared with tanglefoot, although the apparatus soon became 

 filled with earth and pieces of leaves. Various birds, rooks, crows, 

 jackdaws, larks, and even sparrows greatly assisted the destruction 

 of the caterpillars. The pupal stage lasted 19-21 days and the 

 imagines of the second generation appeared on the beet plantations 

 from 16th-19th July, being somewhat earlier along the edges of 

 forests. 



H^ypHani) dHTOMonorimecKaro GoBtiuaHifl no Bonpocy o Mtpax-b 

 6opb6bl Cl» nyrOBblMlj WIOTblJlbKOIWb. [Proceedings of the Entomo- 

 logical Conference on the questions of methods of control of 

 FJilyctaenodes sticticalis, L. (convened by the Uprava (Executive) 

 of the Zemstvo of the govt, of Charkov and held on 20th June 

 1913).] CAar^ov 1915, pp. 82-93. 



The proceedings began with a report by V. G. Averin on the occur- 

 rence of Phlyctaenodes sticticalis in the government of Charkov and on 

 the measures undertaken by the Bureau to assist the population in 

 the control of the pest. At the time of the Conference, the danger 

 from the first generation was already over and it was proposed to advise 

 on the measures to be undertaken against the second generation. 

 The discussion showed that in the majority of cases spraying opera- 

 tions were of little avail, but both I. V. Emelianov and S. A. Mokrzecki 

 were inchned to attribute this failure to technical defects. The latter 

 pointed to the good results which he always obtained by spraying with 

 barium chloride [see this Review, Ser. A, i, p. 359], and suggested that, 

 besides technical defects, the absence of favourable results may have 

 also been due to spraying having been carried out in rainy weather. 

 In his opinion, the effectiveness of this insecticide depends also upon 

 the age of the caterpillars. The conference adopted a resolution 

 affirming that spraying with insecticides must be regarded as the most 

 efiective remedy, if correctly applied, and recommended as subsidiary 

 remedies, covermg the plants with earth, trenches round plantations, 

 and fields, and the use of tanglefoot. 



