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UNITED STATES NATIONAL MUSEUM BULLETIN 224 



posteroapical bristle. The tibia is slender, shorter than 

 the middle tibia, densely pilose ventrally and with a 

 strong, white bristle anteriorly and posteriorly at the 

 apex and quite short bristles dorsally and ventrally. 

 First four segments of the anterior tarsi each with a 

 long, anterior and posterior apical black bristle. Claws 

 extremely long, gently curved and appressed and sharp 

 at the apex. Pulvilli and empodium absent. 



Wings: The wings are slender, with the basal half 

 of the wings strongly but gradually narrowed so that 

 the second anal cell is very narrow, slender and linear. 

 First anal cell wider at margin than at any other part 

 and this cell more widely open than any other genus. 

 In other respects the venation is typically like Lepto- 



gaster Meigen. Both the veins which end the discal 

 cell are of equal length. The two veins which end 

 the second basal cell are fused for some considerable 

 distance distally. Ambient vein complete and alula 

 absent. 



Abdomen: The abdomen is quite long, slender and 

 subcylindrical and considerably longer than the wings. 

 There are eight dorsal tergites. The metasternal region 

 behind the coxa is very greatly elongate; all of the 

 coxa are carried forward far beyond the transverse 

 suture of the mesonotum and the area behind the pos- 

 terior coxa is fully chitinized. 



Distribution: Ethiopian: Dolichoscius francoisi 

 Janssens (1952). 



Sf 



