238 Miss Haviland, Preliminary note on a Cynipid, etc. 



bionomical complex of considerable intricacy. Thus, this Cynipid 

 hyperparasite, equally with its Braconid host, is liable to destruc- 

 tion by the Chalcid or Proctotrypid ecto-hyperparasites ; and, from 

 observations made in the course of this work, the evidence points 

 to the conclusion that where the incidence of Chalcid and Procto- 

 trypid hyperparasitism is high, few of the Cynipids survive, for 

 they are not only dependant upon the occurrence of the host, but 

 share its vulnerability to other parasites throughout their larval 

 life. I attribute to this the fact that fram collections of parasitised 

 aphides, made in the field, there were proportionately more Cynipid 

 emergences in June than in July. Most of the hyperparasites 

 obtained from later collections were external-feeding Chalcids or 

 Proctotrypids ; and the inference is that the later broods of Cynipids 

 suffered from a second parasitisation of their host by other hyper- 

 parasites. 



