﻿200 



PRQCTOTRUPOIDEA. 



\u the course of our investi!:^ation of the parasites of leaf- 

 liopper, several species of an anomalous form belonging to the 

 Proctotrupoid series were bred. These species, I believe, form 

 a genus not yet described, which at present is best located in 

 the Platygasteridae, in the group which contains the genus Inos- 

 Icinnia, Hal. In some respects they remind one of the well- 

 known egg-parasites of the genus Baeus and its allies, in the 

 Scelionidae ; in others of the likewise anomalous genus Baco- 

 iKiira of Foerster. They too are egg-parasites, attacking those 

 leaf-hoppers' eggs, which are not imbedded in the tissues of 

 ]))ants, but such as are entirely external. The eggs that wc 

 found to be attacked by them, were those of such conspicuous 

 leaf-hoppers, as are included in the genera Siphanta, Platybrachys, 

 etc., and of others allied to these. These parasites are of very 

 great economic value in Australia and without their aid, vege- 

 tation in many localities would suffer very greatly from leaf- 

 hoppers of the genus Siphanta, which indeed are, as it is, quite 

 capable of doing damage under certain conditions in that coun- 

 try. In many places, however, we found that from every egg- 

 in nearly every egg-mass that we collected, we bred one or 

 other of these parasites, and further we saw them in extra- 

 ordinary numbers crawling over and ovipositing in eggs in the 

 field. 



They always escape by gnawing a roundish hole in the egg, 

 so that it is very easy to d'Stingui-h between the egg-masses from 

 which parasites have escaped and those from which }Oung leaf- 

 hoppers have emerged. (PI. XI, fig. 2, 3 and 7.) We were not 

 able to pay very much attention to the eggs of such leaf-hoppers 

 as those mentioned above, so that I anticipate that great num- 

 bers of species of these parasites are to be found in Australia, 

 and probal)ly they are represented by similar or cognate forms 

 in other countries. The parasites themselves, when bred from 

 eggs of such species of leaf-hoppers as cover their eggs with 

 white mealy powder, are frequently so disguised by the ad- 

 herence of this same substance, that unless it 'be carefully clean- 

 ed ofif, their proper structure and appearance cannot be made 

 out. 



GENUS AND SPECIES HERE DESCRIBED. 



Aphaiiojitcnts, gen. nov. 

 I. Aphanouwnts bicolor, sp. nov. et typ. gen. 



