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ON THE HYMENOPTEEOUS PARASITES OF 



RHYNCHOTA. 



By Claude Morley, F.E.S., F.Z.S. 



The following account of the species of Rhynchota which are 

 destroyed by parasitic Hymenoptera claims to be no more than 

 a basis of future work upon this fascinating subject. In due 

 time I anticipate that the intercourse between these vampires of 

 the air, whose lives depend entirely upon the extermination of 

 other insects, and the remainder of entomological Orders will 

 become of considerable moment to the horticulturist and farmer. 

 That their restrictive influence upon the propagation of injurious 

 insect-pests is far greater than any that can be directly exercised 

 by man must be instantly granted, in so far as the natural is 

 invariably more efficient than the artificial. Were it but possible 

 to rear these most beneficially destructive flies in confinement 

 and distribute them to localities suffering from the undue abun- 

 dance of, say, the Hop Fly, Rose Aphis, or the various species of 

 Coccids that at times are so fatal to our fruit crops, we should 

 let loose a natural ally the importance of which has never yet 

 been fully appeciated, because so little known. In California, I 

 believe, they are beginning to attempt something of this kind 

 with an ichneumon fly called Ephialtes carbonarius in relation to 

 the Codlin Moth, so destructive both there and here to the fruit 

 of apple-trees. Personally, I am persuaded that in Britain the 

 more efficacious ally is Pristimerus vulnerator, which I myself 

 have bred in some numbers from stored cocllin-infested apples. 

 The first difficulty, however, is in the production under semi- 

 artificial conditions of these extremely shy and retiring flies, which 

 delight in freedom, space, and sunshine. I have bred both sexes 

 from their natural host in some numbers, and attempted to bring 

 about satisfactory nuptise, even going the length of introducing 

 a live and apparently tempting young host-larva. All has in- 

 variably been in vain. I have upon but two occasions in the 



