June-Oct., 1921 Bulletin of the Brooklyn Entomological Society 67 



Characters of the family S3^rphidae. 



Antennae three-jointed; usually with a dorsal arista, rarely 

 with a terminal style ; third vein of the wings without an 

 anterior branch; anal cell acute and prolonged nearly to the 

 wing margin; either a spurious vein present between the 

 third and fourth veins, or a subsquamal plumose filament 

 (the plumula) present, usually both present; empodium 

 bristle-like; hypopygium asymmetrical, an elongated meso- 

 coxal projection present on middle coxae. 



Table of subfamilies of Syrphidae. 



1, Chitinous parts of body thickly punctate; prostigma placed on 



cephalic aspect of thorax, thorax being foreshortened ; ab- 

 domen of both sexes consisting of four visible segments ; 

 arista as short as the width of third antennal joint; spuri- 

 ous vein of anal cell (elsewhere called the anal furrow, 

 see figure of Chilosia wing) very short, not extending as 

 far as anal lobe incision ; eyes faintly pubescent. Medium- 

 sized flies Nausigasterinae. 



- Body not punctate and otherwise not as above 2. 



2, Antennae very elongate and with a termiinal style; anterior 



crossvein joining discal cell at or beyond the middle; 

 usually an adventitious branch extending into discal cell 

 from third vein; face produced downwards, bare; plumula 

 absent ; males holoptic, and with only four visible abdom- 

 inal segments ; females with five abdominal segments. 



Cerioidinae. 



- Antennae without a terminal style, excepting in CalUcera and 



Pelecocera, but these genera have the anterior crossvein 

 joining the discal cell well before the middle 3- 



3, Antennae very elongate, with a bare dorsal arista ; face evenly 



and gently arched, never produced forward at oral margin 

 and entirely clothed with pile; a stigmatical crossvein 

 present; third vein usually (absent only in Mixogaster: 

 rather slender flies with yellow abdominal bands) with an 

 adventitious and free branch projecting into the discal cell; 

 apical crossvein upright or recurrent; both sexes with three 

 to four visible abdominal segments exclusive of genitalia ; 

 males dichoptic Microdontinae. 



- Antennae not elongate and possessing dorsal arista, excepting 



in a few genera, which are without a stigmatical crossvein, 

 and the apical crossvein is parallel with the wing margin 



