114 H. C. EFFLATOUN. 



hairs ; thc pubesceiice on their dorsal surface is inainly blackish, 

 iniuh longer, and the characteristic metatarsus bears on its sharp 

 ridgc a remarkable fringe of long, black, erect and tiifted hairs. 



Wings pellucid, rather grcyish, with the base of the veins 

 light brown and the subcosta and stigma brownish ; Radius 4 + 5, 

 slightly dipped. Squamulae and their fringes white, and their 

 margins yellow. Haltères yellowish-white. 



Female: Very siniilar to the inale l)ut tbe dust and pubescence 

 on the frons and vertex is usually yellowish or even tawny-yellow. 

 The hind nietatarsi, although nearly as swollen as in the maie, are 

 more rounded and do not possess that remarkable sharp dorsal 

 l'idge with its chnractcristic black friitgc. 



J.eiigtli from H 1o 9-^ mm. 



/v. oc'Stitus was originally describcd from West .\ frira (Rio 

 Cassine, Portugese Guinea), wherc it lives together with a closely 

 allied species: E. obliquus. lîezzi (1912)* states that he had received 

 from Becker spécimens from Egypt of the species described abovc 

 {vestitus) which were erroneously classified as ohliquux. Moreover 

 Becker (1902)** describes the female of E. vestitMs undor the narnc- 

 of ohlignu^ and thià description corresponds entircly with thaï 

 of vestitus 



E. vestitus is not a common species in Egypt and is rather 

 local. It is a very interesting fly owing to the fact that it closely 

 mimics the flight of Hymenoptera, and even to a practised eye it 

 is a very difficult matter to distinguish them. I bave watched it 

 at Marg flying abové Polygonum equisetifolium; it does not remain 

 motionless for a second, but continuously moves and vibrâtes its 

 wings ; it rests on the flowers for a short time and suddenly darts 

 away and sits on the sand and tlien back again on thc flowers, 

 rcj^eating this performance over and over again. 



There is no doubt that the larAa foeds on dccaying vegetable 

 matter.*** 



I hâve captured the adult at Shoubra, Marg, Kerdacé, 

 ^^'adi Iloff, Mariout, Fayoum and I believe it to be more widely 

 distributcd. My dates extend from April to October. 



It is known to occur in Syria, Greece, West Africa and no 

 doubt it occurs in many other localities, but, owing to its close 

 j'csemblance to E. ohliquus, probably it occasionally has been 

 confused with the latter. 



*M. Bkzzi.- Ditt. raccolti (!. Loo. Fea, 4.3- 44- A-n)- (M^)- 2,7- (1912). 

 **Th. Becker:. Mitteil. ZooK Mus. Beri., II. 87. 123. (1902). 

 ***Vide p. 104. 



