African Vhlchotomic Diptera. .317 



brown. Legs: femora clotlicd beneath with lon^ and fine 

 brownish hair. 



Nortlicrn Nigeria: S. Bornu, between September and 

 December, 1908 (Dr. H. A. Fuy). 



As stated above, at the end of the description of the fore- 

 going speeies, Chnjsops jmsillula belongs to the well-marked 

 group which also includes C. cUiaris, Lw., C. fuscipennis, 

 Ricardo, and C. hiticeps, Austen, from all of which it can 

 readily be distinguished by its small size and by its dark- 

 coloured abdomeu uot being lighter at the base. 



Chrt/sops inflaticornis, sp. n. 



$ . — Length (3 specimens) 8 to 9'5 mm. ; width of head 

 2'75 to 3 mm. ; width of front at vertex 1*2 mm. ; length of 

 wmg 8 to 8"75 mm. 



Dorsum of thorax marked alternately with greyish olive- 

 brown and smoke-grey longitudinal stripes; abdomen ochra- 

 ceous-buff, dorsum of second and following segments each with 

 a more or less indistinct russet-brotvn transverse band, second 

 to fifth segments inclusive each icith hind margin and a median 

 triangle on bind border pale ; first and second joints of an- 

 tenna shining tawny ochraceous, first joint strongly sivollen, 

 elliptical-oval ; wings ivith costal border and sharply defined, 

 oblique, transverse band, tapering towards hi?id border, mummy- 

 broicn, apical blotch on casta present and below it a fainter 

 infuscation, including tip of icing and extending along hind 

 border as far as axillary cell and anal angle, meeting trans- 

 verse band in fourth or fifth posterior cell ; legs ochraceous, 

 none of the tibice incrassate, hind tibice with a fringe of short 

 hair on outer side. 



Head broad, cream-coloured pollinose, upper half of front 

 yellowish pollinose ; front broad, frontal callus either clove- 

 Ijrown, raw-sienua-coloured in centre above, or raw-sienna- 

 coloured, clove-brown on lower margin and towards each 

 lateral extremity ; frontal callus fairly prominent, in shape a 

 w ide and low triangle, with apex directed upwards and blunt, 

 and the lateral angles rounded off and either in contact with 

 or only narrowly se|)ar;ited from the eyes ; ocelli somewhat 

 widely separate, each ocellus surrounded by a small dark 

 brown spot, the spot encircling each upper ocellus sometimes 

 taking the shape of a narrow triangular streak, extending 

 outwards towards eye; face broad, somewhat arched and 

 prominent, facial tubercles wanting, no shining spot on 

 jowls ; front, face, jowls, and lower surface of head clothed 

 with erect yellowish hair, longest below : palpi clothed with 



