268 



Reh (L.). Uber Einfuhr-Beschrankungen als Schutz gegen die 

 Einschleppung pflanzenschadlicher Insekten. [Import Res- 

 trictions as a Protection against the Entry of Insect Pests of 

 Plants.] — Zeilschr. /. angeiv. Entom., Berlin, iv, no. 2, 1918, pp. 

 189-237. [Received 19th April 1920.] 

 The advantages and disadvantages of importation restrictions and 

 quarantine measures are discussed and many existing laws, including 

 those of the United States, are reviewed. It is almost impossible 

 entirely to eliminate the danger of introducing a foreign pest into a 

 country by this means in cases where the conditions for its entry and 

 establishment are favourable ; its distribution may however be greatly 

 limited by the timely application of quarantine regulations. The 

 importance of field inspection is emphasised. 



Jordan (K. H. C). Uber die Gallmilbe, Oxyjdeuritcs carmatus, Nal., 



ihren Schaden und ihre Bekampfung. [The Gall Mite, Oxj/pleurites 



carinatus, its Damage and its Control.] — Zeilschr f. angew. Entom.. 



Berlin, iv, no. 2. 1918, pp. 238-266, 17 figs. [Received 19th April 



1920.] 



The sickly appearance of horse-chestnut trees {Aesculus hippocas- 



tanum) and the early fall of their leaves has been found to be due to 



a mite, Oxypleurifes carinatus, Nal., the various stages of which are 



here described. The eggs are usually deposited on the leaves, and 



these hatch in from 8 to 10 days. The larvae moult twice at intervals 



of from 6 to 8 days, making the total life-cycle from egg to adult about 



22 to 26 days. The number of generations occurring during the year 



could not be definitely ascertained as it varies according to the fall of 



the leaves. Hibernation occurs under scales of the bark in the vicinity 



of buds and lasts from early autumn to late spring. The damage caused 



by this pest has been greatly reduced in certain cases by the activities 



of Gamasids. 



Nicotine sprays have proved effective against the mites. The time 

 of application depends on the development of the trees. The first 

 spray should be applied about the middle of May as soon as the bud- 

 scales have fallen oft". This should be repeated in about a fortnight. 

 The jet must be directed against the lower surface of the leaves. 



Stellwaag (F.). Das Massenauftreten des Rebstechers {Bi/ctiscus 



betulae, L.) in der Rheinpfalz. [An outbreak of Bi/ctiscus betulae 



in the Rhine Palatinate.] — Zeitschr. f. angew. Entom., Berlin, iv, 



no. 2, 1918, pp. 274-277. [Received 19th April 1920.] 



Byctiscus betulae was very abundant during 1917 in the Rhine 



Palatinate. In addition to vines, willows, poplar, beech and even 



apple and cherry trees were attacked by this weevil. The necessity 



for the enforcement of compulsory remedial measures is emphasised. 



Stellwaag (F.). Cyanwasserstoff gegen die Traubenwickler. 



[Hydrocyanic Acid against Vine Moths.]— Zeitschr. f. angew. 



Entom.,' Berlin, iv, no. 2. 1918, pp. 278-286. 2 figs. [Received 



19th April 1920.] 

 Experiments have been made with hydrocyanic gas as a furaigant 

 against vine pests. The advantages and disadvantages of this method 



