Bombyluidae (Diptera) from Central Afra. 627 
joint with a short point and a rather long style. Thorax with black 
hairs, in front also; the side shows an entire white longitudinal 
stripe, which is continuous with the white spots on the indentation 
of the hind margin of the eyes; pleurae wholly black-haired, some- 
times a few pale hairs in the posterior part of the metapleural tuft. 
Scutellum black. Halteres brownish. Abdomen black; on the 
sides at the base are white hairs ; the third segment bears at base an 
entire but narrow transverse band of white hairs; the sides of the 
abdomen bear dense tufts of black scaly hairs, Legs wholly black, 
with black bristles and black pubescence. Wings hyaline, with 
black veins; the base is black as far as the basal cross-veins ; 
costal cell darkened ; the small cross-vein is broad and with a narrow 
dark margin. Squamulae with a white fringe. 
TyPE 2 and four additional specimens from North 
Nyasa, Nyika Plateau, Rongorwi stream, August 29, 1909 
(Dr. J. B. Davey). 
36. Thyridanthrax abruptus, Loew (1860). 
Allied to the preceding, but showing a more extended 
dark pattern on the wings. The hairs on the front of the 
thorax are yellow. Squamulae with a yellowish fringe. 
Metapleural hairs partly black. Wing veins black. 
A specimen from North Nyasa, Kabwiia stream, 
August 31, 1909 (Dr. J. B. Davey); another from West 
Nyasa, Momberas District, October 1909 (Dr. H. 8. 
Stannus); and one from Northern Nigeria, Minna, 
October 10, 1910 (J. J. Simpson). 
37. Thyridanthrax sp. mdet. 
A single badly-preserved specimen of a grey species, the 
wings of which are hyaline, with the extreme base only 
black. I think that is only a form of the Mediterranean 
T. vagans, Loew. 
North Nyasa, Vua, October 28, 1909 (Dr. J. B. Davey). 
38. Thyridanthrax sp. det. 
A single specimen of another smaller species, allied to 
the preceding one and to 7’ /eweoproctus, Loew (1860), from 
the Cape. 
North Nyasa, Bundi Village, Fuliwa, May 13, 1909 
(Dr. J. B. Davey). 
13. Lsotamia, gen. nov. 
TyPE: Jsotamia daveyt, sp. nov. 
This genus can be regarded as an Hxoprosopa with very 
long proboscis and very narrowed wings, which are almost 
