40 SYJBPHID.iE. 



Head rather wider than thorax ; eyes bare, contiguous in ^ ; 

 frons in S often inflated, with a depression in the centre, in 

 2 broad, with " transverse furrows which run from the sides 

 towards a vague middle longitudinal chanuel which is smooth and 

 is bounded on each side by a linear groove" {Verndl). Face 

 difl[ering slightly in the sexes ; in J central knob more distinct 

 and upper mouth-border less produced, in $ central knob often 

 absent but upper mouth-border very prominent. Antennae short, 

 3rd joint rounded (less so iu subgenus Orthoneura) ; arista bare, 

 nearly basal. Thorax subquadrate, scutellum normal, both wdth 

 short soft pubescence. Abdomen rather short, oval, flattened, side 

 margins rounded, usually metallic. Legs simple, moderately 

 strong. Wings somewhat as in Syrphiis, but the last section of 

 the 4th vein strongly recurrent and often sinuous: 1st posterior 

 and discal cells and anal cells somewhat shortened ; anterior ci'oss- 

 vein distinctly before middle of discal cell. 



Life-historg unknown, but two European species have been bred 

 from* larvce found in the mud of a ditch. 



This genus has been split up and reformed more than ouce, the 

 groups Liogaster and Orthoneura being regarded by some as good 

 genera, by others as subgenera only. The former is characterised 

 by the widely separated eyes iu the 6 , the latter by the strongly 

 recurrent tip of the 4th vein and the elongate 3rd antenual joint. 

 In Chrysogaster, sens, str., the vein is not recurrent and the 3rd 

 antennal joint is short and subquadrate. Other subgenera have 

 been set up which need not be considered here. 



Only one species of this group is Indian ; it falls into 

 Orthoneura. 



Subgenus ORTHONEURA, Ilacq. 



Differing from Chrysogaster, sens, str., by the recurrent 4th vein 

 and elongate 3rd antennal joint (though these characters do not 

 always appear in the same species). Only one Indian species is 

 known. 



Range. Europe, Asia Minor, Siberia, India, Aru Islands, North 

 America, Brazil. 



33. Chrysogaster (Orthoneura) iudica, Brun. 



Chrysoqastcr {Orthoneura) indica, Brunetti, Rec. Ind. Mus. xi, p. 203 

 (i915). 



(S . Head : vertex very small, with a little dark brown hair ; 

 eves contiguous for a moderate space, about half the heiglit of the 

 frons, dark brown, bare; frons shining blue-black, with light brown 

 or greyish hairs ; antennal prominence slight ; face shining blue- 

 black wdth a little whitish hair, mouth-border well produced. 

 Proboscis and palpi blackish-brown. Antennae rather dark brown, 

 3rd joint ovate; arista almost basal. Occiput blackish, not at all 



