﻿Bomhyliidac {Dipterci) from Central Africa. 607 



2. Bûmhylius ornatus, Wiedemann (1828). 



Fifteen specimens of both sexes of this common African 

 species, Soiigvve River, North Nyasa, June 21, 1909 ; near 

 mouth of River Rumpi, May 12, 1909 ; Mwenetete village, 

 Songwe River, June 21, 1909, round cattle (2 ^, 2 f ) ; 

 Florence Bay, November 1, 1909; Deep Bav, October 81, 

 1909; Marimba, Ukasi village, January "l5, 1910 (all 

 from Dr. J. B. Davey). Mzimba West Nyasa, May and 

 June 1909 {Dr. H. S. Stannus). 



2. SystoecJms, Loew (1855). 



This genus, which is of economic importance, is well 

 represented in the collection by numerous specimens 

 belonging to five different species. The larvae live in the 

 egg-cases of locusts, as observed in N. America by Riley 

 (*S^. 07'eas preying on Ocdipod(t atrox) and in Europe by 

 Stepanoff, Schimkewitch and Portschinsky {S. autmunalis 

 and leucopkam^ on Stauronotus maroccanus). 



The species before me can be distinguished as follows : — 



1 (2). Feniiira wliully black ; abdomen with very few black bristles; 



wings tinged at the base with dark brown or blackish. 



allnchis, Loew. 



2 (1). Femora wholly yellow or black at the ba8e only ; abdomen 



with or without bristles ; wings wholly clear or wich a 

 brownish or yellowish tinge at the base. 



3 (6). Abdomen without black bristles at the hind margin of the 



segments ; femora wholly yellow. 



4 (5). Eyes of the male separated ; face with yellow hairs ; hind 



femora with black spines ; wings broadly infuscated at 

 the base ....... robnstvs, sp. n. 



.5 (4). Eyes of the male touching ; face with black hairs ; hind 

 femora with yellow spines ; wings clear at the base. 



simplex, Loew. 



6 (3). Abdomen with black bristles at the hind margin of the 



segments. 



7 (8). Face with black hairs ; hind femora with yellow bristles 



melampogon, sp. cov. 



8 (7). Face with yellow hairs ; hind femora Avith black bristles 



denopteriis, Mikaii. 



3. SystoecJms albidus, Loew (1860). 



The abdomen of this species bears very few black 

 bristles, the most of these being whitish. I think that 



