Asilidxfrom Aden and its neighbourhood. 89 



sentincr a T^mm-species. In this figure the fourth 

 posterfor cell is closed at the margin of the ^mg, whereas 

 in the specimen before me (see my figure, Fl. Hi, hg. l) 



it is open. tvt i,- ;i 



Wiedemann's description was based on Nubian and 



Egyptian specimens. 



13. Hahropogon senilis, n. sp. ^ . 



Cinereous ; thorax with brownish stripes ; abdomen, antennje and 

 legs rufous ; wings hyaline. 



Length 8 mm. 



Head broader than high ; front and face slightly narrower than 

 the eyes ; front not excavated ; face pale yellow, flattened ; mystax 

 yellowish, very compact, but confined to the oral margin. Antennee 

 rufous, as long as the head ; basal joints with some pale bristles ; 

 third joint elliptical, as long as the basal joints together ; termmal 

 style very short, but distinct. Proboscis black, pointed towards the 

 tip ; palpi rufous, with yellow hairs. Thorax, scutellum and meta- 

 notum cinereous ; thoracic dorsum with three broad brown stripes ; 

 the median stripe anteriorly divided by a lighter line ; posterior 

 part of the thorax with pale yellow bristly hairs ; a row of similar 

 hairs at the hind border of the scutellum ; the hairs before the 

 halteres likewise pale yellow. Abdomen cylindrical, rufous, without 

 hairs and bristles, but in well preserved specimens with some greyish 

 dust, which, however, does not much modify the ground-colour ; the 

 front border of the first and sometimes also of the second segment 

 blackish ; genitalia little developed. Legs rufous ; coxse cinereous ; 

 a streak on the upperside of the hind femora, the tip of the hind 

 tibiae, and the hind tarsi, brown ; the legs are rather robust, the 

 hind tibise very slightly enlarged towards the tip ; the first tarsal 

 joint of the fore and middle pair is not longer than the second joint ; 

 in the hind tarsi it is somewhat enlarged and as long as the two or 

 three following joints together ; the legs have a whitish pubescence 

 and weak yellow bristles ; on the underside of the hind femora the 

 bristles are shorter ; the foot-claws are black. Halteres pale yellow. 

 Wings hyaline ; the veins at the base and near the costa rufous ; all 

 the posterior cells open ; third basal cell narrowed towards the 

 margin of the wing ; small cross- vein a little before the middle of 

 the discal cell. 



Three male specimens from Aden. 



