﻿Oil the Boinhyliid Fauna of South Africa (Di2)tera). 89 



right angles -witli the basal one ; the metapleura is bare ; the legs 

 have bristly hiud femora, bristly tibiae and long pulvilli ; the wings 

 are short, destitute of a basal hook, comb, and alula. The first vein is 

 vstraight and the marginal cell not dilated at end ; discal cross-vein 

 placed on the last third of the discoidal cell ; first posterior cell 

 broadly open. 



In the collection are three species, to which I can add another from 

 my own collection ; they may be distinguished as follows : 



1 (6). Proboscis very short and thick, shorter than the thorax, with broad 



terminal labella. 



2 (5). Body clothed with moderately long- hairs, which are of a yellow 



colour ; haltères of male white ; tibiae black. 



3 (4). Species of larger size, at least 10 mm. long; piibescence of a paler 



yellow colour ; ocellar tuft in both sexes and first antennal joint in the 

 male with black hairs above ; female with black hairs on the vertex. 



leucophys, Bigot. 



4 (3) Species of smaller size, not over 8 mm. in length ; pubescence of bright 



yellow colour ; ocellar tnit and first antennal joint in both sexes 

 yellow-haired ; female without black hairs on vertex. 



xanthinus, sp. nov. 



5 (2). Body clothed with exceedingly long and white liairs ; haltères of the 



male with black knob ; tibiae sometimes yellow . cycnv.s. Bigot. 



6 (1). Proboscis thin, longer than thorax and head, with narrow terminal 



labella ; basal joint of antennae black- haired above. 



chio7iens, sp. nov. 



GONARTHRUS LEUCOPHYS, BigOt (1892). 



A species distinguished by the short and thick j^roboscis, the black 

 hairs on the ocellar tubercle and on the base of the antennae in the 

 male, the yellow pubescence and the straight, not retreating base of 

 the upper branch of the cubital fork. 



Originally described from the Cape ; there is a male from Barberton, 

 Transvaal, April, 1911 (H. Edwards). 



In the present species the thii-d antennal joint is very narrow and 

 acute, being much narrower than the first. The hind femora have 

 more numerous spines, 3-4 in number; the middle femora have 

 2 spines. 



GONARTHRUS XANTHINUS, Sp. UOV., cJ , ? . 



Very near the preceding, but at once distinguished by the smaller 

 size, the yellow ocellar tuft, the wholly yellow-haired base of the 

 antennae and the bright yellow colour of the pubescence of the body. 



