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two generations depend on the difference in the meteorological 

 conditions. Dry weather and a high temperature affect all the stages 

 of the pest ; the moths perish in such weather without being able to 

 oviposit or after depositing only a small number of eggs ; the eggs 

 dry up, the caterpillars are smaller in size, and they are either unable 

 to pupate, or the pupae dry up and perish. This is the reason why 

 the second generation is usually less numerous than the first and why 

 it frequently does not appear at all. Besides the vine, these pests 

 live on many other plants, which frequently accompany the culti- 

 vation of the vine and which may either serve to draw away the pests 

 from the vine or afford favourable conditions for the development of the 

 pests before their migration to the vine. A list of 15 species of food- 

 plants, belonging to eight families is given, viz. : — Rhamnus frangula 

 [buck thorn] ; Euonytmis europeus ; Ribes nigrum [black currant] ; 

 R. rubruni [red currant] ; R. grossularia [gooseberry] ; Cornus mas ; 

 Cormis sanguinea [dog wood] ; Primus spinosa [black thorn] ; Acer 

 campestre [field maple] ; Lignstruyn vulgare [privet] ; Syringa per- 

 sicum ; Viburwim lantana [wayfaring tree] ; Viburnum opulus 

 [guelder rose] ; Sambucus racemosa [scarlet-berried elder] ; Hedera 

 helix [ivy]. 



Polychrosis botrana, 8chiff., the bionomics of which are generally 

 similar to those of Clysia, is described. The life of the imago is shorter, 

 being about two weeks. P. botraua suffers also from heat and dry 

 weather, although to a less degree than C. ambiguella, as was observed 

 by Feytaud in France in 1911, when the latter species perished, while 

 P. botrana continued its development. It is also photophobic 

 during the day, but is not attracted by light at night. The 

 caterpillars do not spin a web and do not eat out the lignum of the 

 shoots. The pupae of the second generation remain over the winter. 

 This pest also feeds on other plants and it is thought that it prefers 

 Daphne gnidium to vine. The following list of 19 food-plants is given : 

 Zizyphus vulgaris [jujube] ; Clematis vitalba [traveller's joy] ; Medi- 

 cago sativa [lucerne] ; Trifolium pratense [purple clover] ; Ribes 

 rubrum ; Ribes nigrum ; Rubus fructicosus [blackberry] ; Ampelopsis 

 quiquefolia [Virginia creeper] ; Cornus sanguinea ; Prunus spinosa ; 

 Viburnum lantana ; Ligvstrum vulgare ; Rhus glabra [sumach] ; 

 Rosmarinus ojficinalis [rosemary] ; Galium molugo [bed-straw] ; 

 Silene iiifiata [bladder campion] ; Arbutus unedo [strawberry tree] ; 

 and possibly on certain species of tulip and magnolia. The 

 shading of vine-clusters increases the extent of oviposition, while 

 their exposure to the sun's rays has an opposite effect. Plenty of 

 moisture and the situation of vineyards in wet and low-lying places, 

 tend to increase the rate of infestation, and the cultivation of vines 

 in places protected from wind or in the form of vine arbours or arches, 

 as is usual in Astrachan, also provides conditions favourable to the 

 insects. The close planting of vines has the same effect. The tying 

 of the branches round poles and the espalier method of cultivation 

 afford better protection. " Pinching " must be done before the 

 oviposition has been effected and the watering after the hatching of 

 the caterpillars. Attention must also be paid to the selection of the 

 proper type of vine ; according to Marchal those with short and thick 

 inflorescence, such as " Pignon " and " FoUe Blanche," were more 

 affected than those with long and straggling inflorescence, such as 



