500 



uselessly expended in the air. A useful result would be attainable only 

 with charges that act chiefly in a horizontal plane and that are placed 

 at a very slight depth. The addition of gaseous poisons is useless, 

 because, apart from the resistance of the larvae, the earth is very 

 impermeable, especially where it has been compressed by an explosion. 



Stellwaag (F.). Arsenmittel, Weinbau und Pflanzenschutz. [Arseni- 

 cals. Viticulture and Plant Protection.] — Zeitschr. angew. Ent., 

 Berlin, viii. no. 2, May 1922, pp. 427-436, 4 figs. 



The vine-louse [Phylloxera] was first noticed in Germany in 1874, and 

 40 years later, scarcely 1 per cent, of the German vineyard area was 

 infested, the cost of the measures taken against it during the whole 

 period being about ;^1, 300,000 at par. An equivalent sum was lost in 

 one year (1910) as a result of infestation by vine-moths {Clysia anihi- 

 guella, Hb., and Polychrosis hotrana, Schiff.), which constitute an 

 immense danger that can be, however, combated effectively by means 

 of arsenical sprays. 



Up to 1900 C. amhiguella was the species chiefly involved, and the 

 measures adopted were without any scientific basis, just as they had 

 been during the preceding two thousand years. About 1900, new 

 measures based on investigations on the life-history of the moth began 

 to be apphed. P. hotrana, first noticed as a vine pest in Germany in 

 1899 by Zschokke, began to become important. This moth has a third, 

 autumn generation, a shorter development period and no well defined 

 flight periods, so that it is more difficult to deal with than C. amhiguella. 

 Nicotine sprays proved very useful against these vine-moths. Arseni- 

 cals were tested in 1907 with fair results, but administrative regulations 

 made their emplojonent impossible. By 1915 nicotine was proved to be 

 effective against both the spring and summer generations of the vine- 

 moths, but by 1917 tobacco products were too costly and almost 

 unobtainable, and it became necessary to find a cheap and effective 

 insecticide and to use it universaUy if the vineyards were to be saved. 

 Arsenicals, the cost of which is only a small fraction of that of nicotine, 

 can be incorporated in the lime-copper spray used against Peronospora 

 and satisfy all requirements; in 1921 in the Palatinate alone they 

 were used on a area more than ten times as large as in 1918. The 

 German Ministry of Health has modified its regulations respecting 

 arsenicals to meet the new conditions. 



LiNDiNGER (L.). Zur Reblausfrage. Eine Entgegnung an Herrn 



Borner. [On the Vine-louse Question. A Reply to Herr Borner.] 

 — Zeitschr. angew. Ent., Berlin, viii, no. 2, May 1922, pp. 437-444. 



Borner's criticism [R.A.E., A, ix, 609J of the author's view that the 

 original habitat of the vine-louse [Phylloxera vastatrix] is the shores 

 of the Black Sea [R.A.E., A, ix, 256] is discussed. 



WiMMER ( — ). Ueber das Vorkommen der Knopperngallwespe {Cynips 

 calicis, Burgsd.) in Deutschland. [The Occurrence of C. calicis 

 in Germany.] — Zeitschr. angew. Ent., Berlin, viii, no. 2, May 1922, 

 pp. 445-447. 



Cynips calicis, Burgsd., is well known as the producer of galls 

 on the pedunculate oak [Quercus pedunculata) . These are particularly 

 rich in tannin, and are collected in large quantities in the oak forests 

 of Croatia and Slavonia. 



