57 



Johnson (W. F.). Rhyssa persuasoria in the Counties of Down 

 and Fermanagh. — Irish Naturalist. Dublin, xxviii, no. 10, October 

 1919, pp. 115-118. 



The Ichneumonid, Rhyssa persuasoria, L., is recorded as boring into 

 the bark of silver fir, the wood attacked being dead, but not rotten. 

 In close proximity to the part attacked holes of Sirex gigas were 

 usually found, into which the parasite was seen to insert its ovipositor, 

 and investigations revealed larvae of Sirex gigas immediately beneath 

 the part of bark selected for oviposition. 



Gatenby (J. B.). Notes on the Bionomics, Embryology and Anatomy 

 of certain Hymenoptera Parasitica, especially of Microgaster 

 connexus, Nees. — Linn.. Soc. Jl., Zoology, London, xxxiii, 

 June 1919, pp. 387-416, 3 plates, 15 figs. [Received 8th 

 December 1919.] 



Previous work on the modus operandi of the parasitic larvae of 

 Apanteles and Microgaster is reviewed. Although the parasites of 

 the larvae of Arcfornis chrysorrhoea {Porthesia similis) and Pieris 

 brassicae include Chalcids, Ichneumonids and Tachinids, the majority 

 are Braconids. 



Microga^er connexus, Nees, lays on an average about 30 eggs in the 

 body of small caterpillars of A. chrysorrhoea, and in some cases as many 

 as sixty parasites have been bred from one individual. The parasitic 

 larvae emerge from the' body of the host just about the time the latter 

 is ready to pupate. Soon after emergence they commence spinning 

 cocoons, which may be attached to the body of the host. Hibernation 

 usually occurs in this stage. M. connexus is itself parasitised by an 

 Ichneumonid, Mesochorus pallidus, Brisch., the eggs of which are 

 probably laid upon M. connexus while the latter is still within its 

 larval host. This hyperparasite does not kill the parasite until the 

 latter has spun its cocoon, which the hyperparasite utilises. Mesochorus 

 pallidus has not been bred from Apanteles glomeratus, but another 

 Ichneumonid apparently stands in the same relation to it as does 

 M. pallidus to Microgaster connexus. 



The majority of Chalcidids and Cynipids associated with Aphids 

 are probably hyperparasites, the Cynipid, Allotria flavicornis, having 

 been proved to be so. 



Trabut ( — .). La Defense contre les Cochenilles par les Coccinelles. — 

 Rev. Hortic. de VAlgerie, Algiers, xxiii, no. 8-10, August-October 

 1919, pp. 293-296, 3 figs. [Received 8th December 1919.] 



Owing to the abimdance of Pulvinaria psidii on Ficus the predaceous 

 CoccineUid, Cryptolaemus montrouzieri, has been imported from the 

 United States against it. All stages have been liberated, but it has not 

 yet become estabUshed Imder natural conditions, so that laboratory- 

 bred colonies must be relied upon for insect control. It has also been 

 liberated in orange groves, where it is hoped it will attack Pseudococcus 

 adonidum. It may also prove useful against P. vitis. 



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