232 



MUSCIILE. 



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 : 



'bare. Body bare, more or 



less metallic 1. GYMNOPA. 



Radial vein 



of the visual length. 



Arista 



pubescent. Body pale, with 

 some bristles . 



2. OPOMYZA. 



thinly plumose on both sides 3. DIASTATA. 



with five or six bristles on 



each side 4. DROSOPHILA. 



^very short 5. ASTEIA. 



Genus I. GYMNOPA. 



GYMNOPA, Fal. Oscinid. (1820); Meig. ; Mcq.; Westw.; Zett. Syr- 

 phus p., F. E. S. Eristalis p., F. S. A. Madiza p., Fal. ; Zett. 



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

 latitudine. Frons plana. Facies tuberculata. Epistoma prominens. 

 Antennas facie mnlto breviores; articulus tertius oblongus; arista 

 gracilis, nuda. Abdomen ovatum vel subellipticum, thorace paullo 

 longius. Pedes mediocres. 



Body smooth, shining, bare. Head transverse, as broad as the tho- 

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

 Eyes nearly round. Antennas 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. Prasbrachial 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 Gymnopa inhabit herbage, and frequently occur on win- 

 dows. 



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

 anea> Fal.; Zett. jffinea, antennis nigris, thorace valde convexo, alis 

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



JEneous. Antennas 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 ; prasbra- 

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

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

 parted by full twice its length from the prasbrachial transverse, and by 



