42 Annals of tlie South African Museum. 



deep ; it is clothed, like the vertical triangle, with long, erect, rather 

 strong, black hairs, and only near the sides with some very short 

 yellow ones. Face short but much produced, with rigid black hairs 

 forming a long moustache-like fringe, very much developed and 

 produced horizontally, and extended to the extreme end of the genae, 

 only on the sides, near the eyes, are a few short yellow hairs ; upper 

 areolets of the eyes hardly enlarged. Antennae entii-ely black ; first 

 joint with dark yellowish hairs, Avhich are longer below than above; 

 third joint as long as the two first joints taken together, gradually 

 tapering in a moderately thin point ; proboscis entirely black, straight 

 and thin, 6 mm. long, with the labimn smooth below ; palpi short, 

 club-shaped, black with paler base. Thorax clothed with rather long 

 pale yellowish hairs, Avhich viewed from the front show a whitish tinge ; 

 on the pleurae they are a little longer but scarce, and white with a 

 sericeous sheen ; on the uotopleural line there is a distinct stripe of 

 darker, sometimes blackish, hairs ; bristles whitish yellow ; metapleural 

 tuft rich and white. Scutellum entirely black, clothed with long hairs 

 like those of the thoi'ax, with no distinct bristles on the hind border, 

 or at least they are concealed within the hairs. Squamae whitish 

 yellow, with white fringe ; halteres with white knob. Abdomen 

 entirely black, clothed like the thorax but the hairs are whiter, with a 

 silvery sheen ; there are rather numerous and distinct black bristles 

 on the sides of the last segments ; venter with whitish hairs and black 

 erect bristles along the middle ; genitalia red, of medium size. Legs 

 yellow, with tarsi and coxae black ; base of the 4 anterior femora and 

 end of the hind tibiae more or less broadly infuscate ; they bear white 

 scales, few white hairs on the base of femora, and black spines. Spicules 

 of the 4 anterior tibiae well developed ; front femora with 1-2 short 

 spines, middle femora with 3-4 long spines, hind femora with 7-8 very 

 long spines, the other rows being less developed ; coxae with long and 

 dense white hairs ; claws thin, black, with narrowly red base ; pulvilli 

 whitish, long. Wings with the usual venation, but with black veins ; 

 they are strongly infuscated from the end of the first longitudinal 

 vein to the end of the second basal cell and to the base of the alula, 

 which has a yellowish fringe ; basal comb of great size, black, pale 

 tonientose basally ; discoidal cell obtuse at end, its terminal vein as 

 long or even a little longer than the discal cross-vein. 



SYSTOECHUS ALBIDTJS, Loew (1860). 



Very near the two preceding species, but distinguished by the black 

 femora and by the more numerous abdominal black bristles. A single 



