Bombyliidae (Diptera) from Central Africa. 649 
yellowish ; claws yellow at the base, with a small tooth. Wings 
broad and long, greyish hyaline, the anterior half darkened, its limits 
being irregular and not, sharply defined; the veins are a little 
margined with fuscous. Venation asin the preceding species, but 
the origin of the second longitudinal vein opposite to the small ecross- 
vein ; the first posterior cell is, moreover, not so narrowed at the base. 
Type ¢ and 2, and two additional specimens from North 
Nyasa, bush near Wovwi stream, November 27 and 28, 1909 
(Dr. J. B. Davey). 
69. Hxoprosopa heterocera, sp. nov. 
?. Length of the body 11 mm., of the wing 10mm. 
A black species with unspotted wings, readily distinguished by the 
colour and the shape of the third antennal joint, which approaches 
to that of the species of Thyridanthrax of the group represented by 
T. elegans. 
Head black, with white tomentum and with black erect hairs 
on the frons ; face projecting, with white hairs on the sides; occiput 
with argenteous scales at the margins of the eyes ; proboscis black, 
not projecting. Antennae with the first two joints short, black, the 
first with short black hairs; third joint very long, more than twice 
the first two together, of linear shape, not pointed, obtuse at the tip, 
with a very minute less distinct style; its colour is yellow, darkened 
towards the end. Thorax black, with grey hairs and black bristles ; 
hairs on the pleurae white. Halteres black, with the knob white 
below. Scutellum black, yellow at the margin. Abdomen black, 
with white tomentum ; first segment with tufts of white hairs on 
the sides; spines of the female genitalia long, dark yellow. Legs black, 
black pollinose and with black spines ; hind claws small, yellow at 
the base, with a small tooth. Wings uniformly smoked, the second 
posterior cell and the base of the discal cell beinga little more clear ; 
base and costal cell yellowish-brown, first basal cell and the middle 
of the subcostal cell darkened. Small cross-vein placed before the 
middle of the discal cell, the second longitudinal vein beginning 
opposite it ; first posterior cell a little narrowed at the end, second 
and third of almost equal width ; discal cell not broader than the 
second basal cell, which equals it in length; third posterior cell 
very short. Veins yellow towards the base, blackish at the end ; 
basal comb black, very small. 
TyPE 2, from North Nyasa, Marimba, near Chia River, 
January 21,1910 (Dr. J. L. Davey); a single specimen in 
not very good condition. 
