640 Prof. Mario — Report on a Collection of 
Head wholly black ; face projecting, the hairs black, with a black 
fringe, towards the margins of the mouth; frons narrow for a 
female, clothed with long black hairs and sparse yellow pubescence, 
which is also to be seen on the face ; occiput with short grey pubes- 
cence and white tomentum at the indentation of the eyes. Antennae 
black, long; first joint twice as long as the second, which is globular 
and sometimes of a dark reddish colour; third joint narrow, elon- 
gate, twice as long as the two basal joints together ; style short, only 
half as long as the third joint, bearing a distinct terminal bristle. 
Proboscis black, a little projecting. Thorax and scutellum black ; 
the hairs of the collar and of the sides are yellow; pleurae clothed 
with black hairs, but on the propleurae there is a golden yellow 
tuft ; metapleural tufts black; the bristles are long and black. 
Squamulae black, with a white fringe ; halteres black, with greyish 
knob. Scutellum with long marginal black bristles. Abdomen 
entirely black; first segment with a tuft of yellow hairs on the sides, 
the others showing only black hairs ; the bands of tomentum on the 
segments are yellowish before and whitish behind ; the patches of 
large black scales are on the sides of the segments from the second 
to the last. Venter black-haired ; spines of the female genitalia red. 
Legs entirely black, with black pubescence and black spines; ungues 
black, with the tooth long. Wings long and narrow; the costal 
third is blackish, but showing a graduated passage to the posterior 
darkened portion ; cross-veins with indistinct dark borders; the 
basal comb and the prealar hook are black. No stumps of veins; 
small cross-vein placed on the first third of the discal cell and a little 
after the origin of the second vein; discal cell very long and narrow, 
not broader than the second basal cell; first posterior cell very 
narrowed at the end, second and third of equal width ; the trans- 
verse vein between the discal and the second posterior cell is very 
strongly S-shaped. Prediscoidal spot whitish. 
TYPE 9, from North Nyasa, Wovwi stream, near Deep 
Bay, May 14, 1909 (Dr. J. B. Davey); three additional 
specimens from West Nyasa, Mulowe and Nsisga (Dr. H. 
S. Stannus); another specimen from Nyasaland, Blantyre, 
April 25, 1910 (Dr. J. #. 8S. Old). 
54. Exoprosopa sigmoidea, sp. nov. 
3. Length of the body 12 mm., of wing 13 mm. 
A species belonging to the group of E. dimidiata, but very 
distinct owing to the strongly S-shaped cross-vein between the discal 
cell and second posterior cell. 
Head black, with grey pubescence and black erect hairs on the 
frons ; face projecting; mouth edges with a pale fringe, with 
