On the Post-Embryonic Development of certain 

 Chalcids, Hyperparasites of Aphides, 



with Kemarks on the Bionomics of Hymenopturous Parasitea 



in General. 



By 

 Maud D. Havilaud, 



Research Fellow of Newnham College, 



With 7 Text-figures. 



Introduction. 



In the summers of 1919 and 1920, certain hyperparasitic 

 Chalcidoidea were reared from material collected in the field 

 for the study of two hyperparasites of aphides, the Procto- 

 trypid, Lygocerus (5), and the Cynipid, Charips (6). 



The following is an account of the post-embryonic develop- 

 ment of two common forms, which were obtained in consider- 

 able numbers from the cocoons of the Braconid, Aphidius 

 ervi, Hal., a parasite of Macrosiphum urticae, Kalt., 

 an aphid that infests the stinging nettle. 



I would here express my sincere thanks to Professor Stanley 

 Gardiner, who gave me facilities to carry out the work in the 

 Zoological Laboratory, Cambridge ; and to Mr. J. Waterston 

 of the British Museum (Natural History), who kindly deter- 

 mined the species of Chalcidoidea submitted to him. 



BlONOMIGAL AND SYSTEMATIC POSITION. 



The two species now considered belong to the sub-family 

 Sphegigasterinae of the family Pteromalidae, which is, accord- 

 ing to Ashmead, the largest group of the Chalcidoidea, and the 

 most ditiicult to classify. 



Asaphes vulgaris, Wlk., belongs to the tribe Asaphini, 

 the majority of which are said by Ashmead to be parasitic 

 on Aphidiidae and Coccidae (1). 



