209 



completely, but on young turnips the upper parts of the roots are 

 attacked, with the result that the growth of the plants is stopped and 

 they become dwarfed and mis-shapen. On clover, chiefly red clover, 

 they gather in the flowers at the time when the seeds are formed and 

 destroy them. On rye, they occurred in such numbers that at the 

 threshing, the workers were made sick by the stench from the crushed 

 bugs. 



As regards control measures, careful observations must be made in 

 order to detect the occurrence of this pest in good time. The egg 

 clusters, containing about 50 eggs, can then easily be destroyed. It 

 is essential to eradicate all weeds, as these furnish the bugs with good 

 breeding places. The nymphs can be collected with nets or destroyed 

 with sprays such as 2 to 4 per cent, lysol emulsion, or tobacco or quassia 

 sprays. The imagines may also be collected with nets. The attacks 

 on young turnips can be prevented by covering the roots with earth. 



DoBRODEEv (A. I.). BMHorpaflHbifl nncTOBepTHM, flByntiHan h rpo3- 

 Aeean, M Mtpu 6opb6bi Cb hmmh no HOBtMiuHM-b HSCJitAoeaHiflM-b. 



[Clysia ambiguella, Hb., and Polychrosis botrana, Schiff., and 

 methods of controlling them according to the latest researches.] 

 — «TpyAbi BioponodHTOMonoriH VseHaro KoMMTeTa Fnae. Ynpae. 

 3. M 3.» [Meynoirs of the Bureau of Entomology of the Scientific 

 Committee of the Central Board of Land Administration and 

 Agriculture], Petrograd, xi, no. 5, 1915, 37 pp. 



Of the five species of Tortricidae which are found on the vine, 

 Clysia ambiguella and Polychrosis botrana are mainly dealt with, the 

 remaining three species, Sparganothis {Oenophthira) pilleriana, Cacoecia 

 costana and Tortrix loeflingiana, being less important. Polychrosis 

 viteana, Clemens, which does enormous injury to vines in America, 

 is considered to be identical with P. botrana. Clysia ambiguella has 

 two generations yearly. The imago appears in spring, issuing from 

 the wintering pupae in the first half or the middle of May. The imago 

 requires moisture especially during the period of oviposition, and 

 accordingly appears in larger numbers and multiplies more freely 

 in damp places, and during w^et summers. The life of the imago of 

 the first generation lasts about three wrecks, that of the second not 

 more than one week. The females oviposit singly on the blossoms, 

 not on unfolded buds, on the bracts or pedicels of vine, mostly at dusk 

 or during wet days, each female depositing from 50 to 70 eggs or more. 

 The total number of eggs in their ovaries is 120-160, but they never 

 deposit the whole of these. In dry weather a great proportion of the 

 eggs dry up and perish. The caterpillars, which emerge from the 

 eggs during the night or on wet days, spin a web round the buds and 

 feed inside it ; for protection against bad weather they spin a thicker 

 " tube " inside which they pass the day, issuing at dusk to feed. 

 The pupal stage lasts two weeks, the emerging females ovipositing on 

 the grapes. These females of the second generation deposit fewer 

 eggs, approximately 15-30, which develop in about four days, and 

 the caterpillars eat into the grapes when half out of the eggs ; they 

 do not spin any web, living inside the grapes, and leaving them only 

 when the latter become too soft. The differences in the habits of the 



