232 musciDjE. 



The species of this subfamily are numerous, and of small size ; 

 they frequent recent or decaying vegetable substances. The ge- 

 nera here described may be grouped thus : — 



f bare. Body bai'e, more or 



less metallic . . . . 1. Gymnopa. 



Radial vein- 



-of the usual length. 

 Arista . . . .« 



pubescent. Body pale, with 



some bristles .... 2. Opomtza. 



thinly plumose on both sides 3. Diastata. 



with five or six bristles on 



each side 4. Drosophila. 



^vcry short 5. Asteia. 



Genus I. GYMNOPA. 



Gymnopa, Fal. Oscinid. (1820) ; Meig. ; Mcq. ; Wcstw. ; Zett. Syr- 



pJms p., P. E. S. Eristalis p., F. S. A. Mudiza p., Fal. ; Zett. 

 Corpus parvum, glahnim, nitens, nudum. Caput transversum, thoracis 



latitudine. Froiis plana. Fades tuberculata, Epistoma prominens. 



Antenuce facie miilto breviores ; articulus tertius oblongus ; arista 



gracilis, uuda. Abdomen ovatum vel subellipticum, thorace pauUo 



longius. Pedes mediocres. 



£odi/ smooth, sMnbig, bare. Head transverse, as broad as the tho- 

 rax. Front flat. Face tuberculated. Epistoma prominent, angular. 

 Eyes nearly round. Antennae very short, not near reaching the epi- 

 stoma ; third joint oblong, a little longer than the second ; sixth slen- 

 der, setiform, bare. Thorax more or less convex. Wings of moderate 

 size, or rather short. Pra3brachial vein ending at the tip of the costal. 

 Abdomen oval or nearly elliptical, a little longer than the thorax. Legs 

 of moderate length and thickness. 



The Gpmiopce inhabit herbage, and frequently occur on win- 

 dows. 



1. subsultans, F. E. S. iv. 304. 96 (1792); Meig.; Mcq.— 

 anea, Fal. ; Zett. JEnea, antennis nigris, thorace valde convexo, alls 

 limpidis, halteribus albidis, tarsis posticis fulvis. Long. 1 ; alar. 2 lin. 



Mneous. Autennaj black. Thorax very convex. Wings limpid ; 

 costal vein ending on the hind border near the tip of the wing ; sub- 

 costal ending before one-third of the length; radial ending at much 

 beyond three-fourths of the length ; cubital ending at the tip ; prtcl)ra- 

 chial ending at the tip of the costal ; pobrachial angular at its junction 

 with the diseal transverse ; discal transverse straight, slightly oblique, 

 parted by full twice its lengtli from the i)r<isbrachial transverse, and by 



