309 

 Adrianov (A. P.). OTMeiT* no noneewM-b BpeflHTejiHin,. [Report on 



pests of field crops. ]—« OTHeT"b A"bflTeJlbHOCTM SHTOMOnOFM- 

 seCKaro Bwpo aa 191 3- 1 9 14 r.r.» [Report on the work of the 

 Entomological Bureau (of Kaluga) in 1913-1914.] Published by 

 the Zemstvo of the govt, of Kaluga, Kaluga, 1914, pp. 67-88 ; 

 12 figs., 1 chart. [Received 4th May 1915.] 



This report is almost entirely devoted to observations on various 

 species of Elateridae, conducted in the district of Kozelsk, Kaluga, 

 where outbreaks of these pests have occurred since 1912. The adults 

 appeared early in May, the great majority of the insects being Limonius 

 aeruginosus, 01., which disappeared on 28th June. Agriotes linealus, L., 

 was on the wing until 7th July, Agriotes sputator, L., until 16th June, 

 while Agriotes obscurus, L., and Athous niger, L., occurred in small 

 numbers. The maximum number was present about the middle of June, 

 during the blossoming of lye, the inflorescence of which appears to 

 be the favourite food. The imagines of L. aeruginosus were specially 

 active during clear, warm days, while those of the genus Agriotes are 

 found in somewhat greater numbers during the evenings. The beetles 

 occurred mostly on winter-sown crops, less frequently on sunmier-sown 

 ones, on clover, in meadows and on boundaries of fields. The females 

 of Agriotes lineatus and A. sputator oviposited in the earth, eggs left 

 on the surface perishing. The eggs and larvae of A. lineatus and 

 A. sputator are described and a table is given showing the growth of 

 these larvae during the first year of their hfe. Agriotes larvae in 

 captivity eat sugar-beet and carrots, in the presence of which they 

 did not touch potatoes. They also attacked each other, and 

 they Avere observed to kill the larvae of Bibio marci, L. The 

 larvae of Athous niger did not touch either beet or carrots. The 

 pupae occur in the soil at a depth of 3 to 6 inches, at which depth 

 the larvae also were usually fomid. The pupal stage lasts 2 or 3 

 weeks, but the period over which pupation occurs extends over 

 the whole of July and August. One ploughing therefore of the soil 

 during the pupation period will only lead to the destruction of a small 

 percentage of pupae. Experiments are described on the influence of 

 mineral manure (basic slag) in minimising the damage to crops, but 

 they proved that the larvae were practically not affected. HeaAry 

 rains, producing a large amount of moisture in the upper strata of the 

 soil, drive the larvae deeper down and thus the amount of rainfall 

 may affect them. 



The other pests of field crops reported during the year were : 

 Anisoplia cyathigera, Scop., adults of which were first observed on rye 

 on 17th June, their numbers increasing to the maximum at the end 

 of that month and the insects disappearing in the middle of July ; 

 no serious damage was caused by them. Anthothrips aculealus, F., 

 was frequently found in rye ears ; Oclisenheimeria taurella, Schiff., 

 occurred everywhere ; Hydroecia nictitans, L., Trachea basilinea, Schiff., 

 Euxoa segetis, Schiff., and Feltia exclamationis, L., were also very 

 common. 



