﻿On the Bomhijllid Fauna of South Africa (Dipfcra). l5l 



2-i (23). The above-named vein short and straight. 



25 (26). Metapleural tuft entirely reddish ; discoidal cell not dilated at end ; 



basal joints of antennae black ; abdomen of male with silvery lateral 

 patches ...... dimidiata, Macq. 



26 (25). Metapleural tuft entirely black; discoidal cell dilated at end and 



ai)pendiculate ; antennae red at base ; abdomen not silvery. 



dilatata, sp. nov. 



27 (4). Wings not properly dimidiate, even if the costa is infuscated or sti-iped. 



28 (37). Abdomen of conical shape, pointed at end, very often red ; terminal 



vein of discoidal cell short, straight, but placed obliquely, and there- 

 fore the upper angle of discoidal cell is an acute one {punctulata- 

 group). 



29 (30). Front tibiae distinctly spinulose ; wings with a brown fore-border 



and with dark spots on cross-veins and bifurcations. 



punctulata, Macq. 



30 (29). Front tibiae smooth ; wings without such a pattern. 



31 (34). Wings with a broad brown fore border. 



32 (33). Dark fore border less intensive and less defined, extending to the 2nd 



basal cell and on a part of the discoidal cell . parvula, nom. nov. 



33 (32). BroAvn fore border well defined, not extending to the discoidal cell or 



2nd basal cell . .... stannusi, Bezzi. 



Wings with a narrow, yellowish, or brownish fore-border. 

 Basal joints of antennae and legs entirely black ; cross-veins infus- 

 cated, abdomen red on the sides . . . inaequalipcs, Loew. 

 Basal joints of antennae and legs red ; cross-veins less infuscated ; 

 abdomen broadly or wholly red . . . batrachoides, Bezzi. 

 Abdomen not conical and mainly black ; terminal vein of discoidal 

 cell straight and perpendicular, its upper angle therefore not acute, 

 the cell being truncate oiitwardly. 



Wings with broad and well-defined black spots on cross-veins and 

 bifurcations {halloplern-gvoni:)) . . . balioptera, Loew. 



Wings not punctate, or only with less defined shading on the cross- 

 veins (bicsiris-group) .... luteicosta, Bezzi. 

 Wings entirely hyaline, without any distinct dark pattern (stupida- 

 group) ..... parvicellula, sp. nov. 



A. GrROUP FUSILLA. 



This small group, which is made distinct by the presence of hyaline 

 fenestrae in the dark part of the wings, included only the West 

 African species j^it'Stlla, Macq., and jacchoides, Bezzi. A third South 

 African species is now added to it. 



ExOl'ROSOPA (ExOPKOSOPA) FORMOStTLA, sp. UOV. 



An elegant species very distinct from all the other South African 

 species of the present subgenus on account of its hyaline fenestrae in 

 the black part of the wings. 



