92 Mr. F. M. van der Wulp on 



vein, wliicli is rufous ; the costal vein is not prolonged round the 

 hind margin of the wing, but terminates just beyond the upper 

 branch of the third vein ; the first basal cell and the first posterior 

 cell are very narrow ; the latter is closed near the margin of the 

 wing ; the second and third posterior cells are imperfect, as the 

 veins separating them do not reach the margin ; the small cross-vein 

 stands upon the first third part of the discal cell. 



Several specimens of both sexes, from Aden and Shaik 

 Othman. 



This species seems to be closely allied to D. hrachyptera, 

 Low (Dipt. faun. S. Afrika's, p. 126), but I cannot unite 

 them, the hairs and bristles in the Aden species being 

 without exception whitish, whereas in D. hracJiyptera black 

 bristles are mingled with the white. 



AsiLlN^. 



17. Promachus 7'ectangularis, Low. 



Promachus rectangularis, Low, Neue Beitr. zur Kenntn. 



der Dipteren, ii, p. 5. 

 * ? Syn. Urax cinctipes, Walk., Entomologist, v, p. 258. 



Four specimens (2 $, 2 $) from Aden, Lahej, Shaik 

 Othman and Haithalhim. 



They agree fully with Low's description. The synonymy 

 of I!7-ax cinctipes, Walk, was already stated by Low 

 (Zeitschr. f. d. ges. Naturwiss. xlii, p. 108). I give a 

 sketch of the winor, PI. Ill, fior. 4. 



Low's specimens were from Massawa, those of Walker 

 from Wadi Ferran (in Arabia). 



18. Philodicus gracilis, n. sp. ^ $. 



Cinereous ; thorax with brown stripes ; abdomen with black 

 •dorsal spots ; tibite rufous ; wings hyaline with the tip grey. 



Length 19-22 mm. 



Head whitish ; face clotlied with white hairs ; mysta.x white or 

 pale yellow, confined to the oral margin, sometimes with one or two 

 black bristles at the sides ; beard snow-white ; occiput grey with 



* Erax cinctipes is not amongst those types of Walker which are 

 preserved in the British Museum Collection ; the type specimen of 

 E. cinicolor is a Promachus and according to Low is identical with 

 P. ruppelli Low. The two species are very near together and may 

 possibly be identical. — J. W. Yerbury. 



