255 



beneath the frame serve to disturb the flea-beetles, which rise and are 

 secured on the net. This arrangement proved useful in the case of 

 low-growing plants, as there is only a small space in which the flea- 

 beetles can attempt to escape. For tall plants insecticides are more 

 suitable. The apparatus described in the preceding abstract proved 

 fairly useful in the case of cabbage, but injured kohlrabi and radishes. 



KoRFF ( — ). Schadigungen an Roggenahren, sog. Kornfrass. Ahren- 

 schaden an Liesch- (Timothee-) Gras. [Injuries to the Ears of 

 Rye. Ear Injury in Timothy Grass.] — Nachrichtenblatt Deutschen 

 Pflanzenschiitzdicnst, Berlin, i, no. 2. 1st August 1921, pp. 12-13, 

 [Received 13th March 1922.] 



Numerous complaints have been made of injury by thrips to the 

 ears of rye. The injury ceases when the ear comes out of the leaf- 

 sheath, but at the point where it has occurred the grain is absent in 

 the ear. The only available measure is to stimulate growth so that 

 the danger period may be as short as possible. 



The flower clusters of timothy grass are injured by the larvae of a 

 midge, Cleigastra flavipes, the great abundance of which appears to 

 be due to premature warmth in spring and drought in early summer. 

 Direct measures are not feasible, so that recourse must be had to deep 

 ploughing. This is all the more advisable as it is not known whether 

 the generation noticed here is followed by others in the course of the 

 year. 



Gefahrliches Auftreten des Wiesenziinslers, Phlydaenodes stidicalis, L. 

 [A Dangerous Occurrence of P. stidicalis.] — ■ Nadir iditenblatt 

 DeiUsdien Pflanzensdintzdienst, Berlin, i, no. 3, 1st September 

 1921, pp. 19-20. [Received 13th March 1922.] 



During the summer of 1921 the sugar beet web worm, Phlydaenodes 

 stidicalis, L., partly destroyed the beet crops in Jugoslavia, Bulgaria 

 and Hungary. It then appeared in Germany, having probably spread 

 from Austria to Silesia. The Plant Protection Institute in Vienna 

 advises the following measures : Where patches of beet are attacked 

 and it is desirable to save neighbouring fields without considering the 

 infested plants, they should be covered with straw (24 to 30 cwt. per 

 acre) and burned, or they may be sprayed with a solution of lye. 

 Infested plots may be isolated by means of trenches or tarred boards 

 and the larvae collected and destroyed. 



BoRNER (C). Ueber die Sanienmg von Reblausherden durch Anbau 

 gepfropfter Reben. [The Cleansing of Vine-louse Centres by 

 planting Grafted Vines.] — Nachrichtenblatt Deutschen Pflanzen- 

 schutzdienst , Berlin, i, nos. 4 & 5, 1st October & 1st November 

 1921, pp. 25-26 & 34-36. [Received 13th March 1922.] 



Official action in Germany against the vine-louse [Phylloxera] has 

 hitherto consisted in destroying infested vineyards, the replanting of 

 which was permitted with the old European varieties of vine, grafted 

 \'ines with immune or resistant stocks being prohibited. There is 

 in Germany a movement in favour of the latter in view of the success 

 achieved in other countries, and much experimental work is being done. 

 The author recalls his early work on immunity [R.A.E., A, ii, 156] 

 showing that Phylloxera pervastatrix cannot adapt itself to certain 



