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BuRKHARDT (F.) & VON Lengerkex (H.). Beitrage zur Biologie des; 

 Rapsglanzkafers [Meligeihcs aeneiis, Fabr.). iContributions to the 

 Biology of M. aeneiis.] — Zeitschr. angew. Entom., Berlin, vi, no. 2, 

 Februan- 1920, pp. 270-295, 32 figs. [Received 2nd December 

 1920.] 



This paper contains a detailed account of the first part of the authors' 

 investigations on Mcligethes aeneiis, F., the chief enemy of rape and 

 turnip in Germany, and deals with the life-history and injury of the 

 beetle from its first appearance in spring up to the emergence of the 

 new generation, i.e., from April to the end of June. The morphology 

 and habits of M. viridescens are identical with those of M. aeneus. 

 Investigations on Cetithorrhynchns napi, GylL, are still being 

 carried on. 



The larvae of M. aeneus do no damage, as they feed exclusively on 

 pollen, without, however, injuring the infested flowers. They may 

 cause self-pollination, or plav an important role as pollen-carriers. 

 [R.A.E., A, viii, 488, 542]. 



The adults appearing in spring may do great harm to the crops,, 

 much depending on the condition of the plants at the date of infestation. 

 If the flowers are already open the beetles are able to feed at once on 

 the pollen, but in a cold spring the buds are still closed when the beetles 

 appear and serious injury may be done. 



It is therefore necessary to select early flowering varieties in order 

 that bud injury may be prevented. The attempts being made to raise 

 such varieties are therefore calculated to solve the problem of combating^ 

 this pest. 



Herold {W.). Zur Kenntnis von Agrotis segekim, Schiff. (Saateule)^ 

 n. Die herangewachsene Raupe. [A Contribution to the Know- 

 ledge of Eitxoa segetnm. II. The mature Caterpillar.] — Zeitschr^ 

 angew. Entom., Berlin, vi, no. 2, February 1920, pp. 302-329^ 

 7 figs. [Received 2nd December 1920.] 



This paper on the later lar\-al stages of Euxoa {Agrotis) segetnm,. 

 which are those chiefiv injurious, supplements one already noticed 

 [R.A.E., A, viii, 271]. ' 



A combination of chemical and physical measures gives excellent 

 results in combating the caterpillars. It was found that if infested 

 fields are strewn with kainit the caterpillars will migrate and may 

 be trapped in trenches. On a large-scale experiment, the apphcation 

 of kainit was followed by rain, and a mass migration was observed,, 

 very large numbers of the caterpillars being taken in the trenches. 

 The mature larvae are unable to chmb slopes of over 35°, and the sides 

 of the trenches should be constructed at an angle of 45°, which 

 effectually prevents escape and yet guarantees that the trench will 

 maintain its shape. The trapped caterpillars should be collected 

 eacli morning. In loose ground some may escape b}- burrowing, but by 

 raking the bottom of the trench most of them can be recovered. At 

 the bottom of a 12-inch-deep trench the caterpillars appear unable to 

 burrow upwards to the surface, though they are known to be able to 

 travel underground for over 3 ft. in a horizontal direction. This would 

 explain why they are usually found near the surface, at a depth much 

 exceeded by the roots of their food-plants, and why they hibernate 

 at a depth of 4-6 inches only. 



