SIGNIFICANCE OF STEGOMYIA FASCIATA IN WEST AFRICA. 241 



are two parallel yellowish or whitish lines running the whole length o£ the 

 thorax. Sciitellum very marked, owing to its being completely covered with 

 silvery white scales. Pleurae with several patches of brilliant white scales. 

 Abdomen dark, with white bands on the bases of the segments. Legs black, 

 the femora for the most part pale beneath, in many cases with a distinct 

 white line running from the base almost to the apex and situated on the inner 

 surface, a white spot is also visible at the apex ; tibise black ; the first and 

 second pair of legs with two white bands on the tarsi, the hind pair with five 

 white bands, the last joint being wholly white. 



Wings with the veins darkly scaled, the upper fork cell being distinctly 

 longer than the second and its base slightly nearer the root of the wing. 



Length 3*5 to 5 mm. ; the average length is about 4*5 mm., but very small 

 specimens are often met with. 



The following descriptions of two closely allied species of mosquitos may 

 assist the student in determinijig Stegomyia fasciata : — 



Stegomyia (Scutomyia) sugens, Wiedemann. 



Characters as seen wider a lens, X 16 : — Head black, with a thin median 

 whitish line and a white patch on each side ; palpi black, white at tip ; 

 })roboscis black. Thorax dark brown with several scattered whitish scales 

 giving, under the hand-lens, the appearance of a fairly distinct broad median 

 pale line : there are also pale areas laterally. On the anterior portion may 

 also be seen four silvery white spots, two on each side and somewhat widely 

 separated. Scutellum whites pleurae with patches of white. Abdomen deep 

 black, with white bands on the bases of the segments. Legs black ; the 

 femora with a white spot at the apex and a distinct white ring a short 

 distance from it, rather pale ventrally. The tibige of the fore and mid legs 

 with a somewhat indistinct white band towards the basal half, those of the 

 hind pairicith a very marhed hand 7iear the centre *. The tarsi of the first two 

 l)airs with three narrow white bands, those of the last pair with five broad 

 bands, the last joint being all white. 



Wings with the veins darkly scaled, the first fork cell being longer than 

 the second, their bases being almost level. 



Length 4-5*5 mm. 



Stegomyia (Kingia) africana, Theobald. 



Characters as seen under a lens, x 16 : — Head black, with a yellowish spot 

 in the middle ; proboscis black ; palpi black, with the tips white. Thorax 

 black, with two short glittering lines directed upwards on the anterior part, 

 and a similar small spot at the base of each wing ; scutellum white ; pleurae 



* According- to Theobald (Moii, Culicid. i, p. 301) this tibial band is not present in all 

 specimens. 



