A Monograph of Egyptian Dipiera. 



CYCLORRHAPHA 



ASCHIZ A 



SYRPHOIDEA 



Syrphidae 



GEISERAL CIIAUACTERS OF THE I AMILV. 



Siiiall to rather large Aies wliich do not possess a frontal suture 

 bladder and witîiout any distinct chaetotaxy. Head as broad as tlie 

 thorax or a little broader, sometinves clongate or produced in thc 

 lower part. Frons more or less produced. Face niotlerateiy broad, 

 usually more or less pubesoent and clothed with dust, but never 

 bristly, and sometimes quite bars, nevcr with longitudinal furrows 

 or latéral ridges; usually it retreats below the antennae, and tlien 

 is produced into a central knob, aft&r which it is excavated and 

 again produced to the upper mouth-edge. Occiput usually shallow 

 and bearing dust and pubescence which is continued to the vertex; 

 fréquent ly the occiput is widened about the middb through an 

 inward bend of the eye. Vertex more or less triangular and never 

 bearing any bristles. Ocelli alw^ays présent. Frons more or less 

 produced, sometimes conspicuously, and never bearing any bristles. 

 Eyes large, bare or j^ilose, usually touching, or at least approximat- 

 ed in the maie, and well separated in ths female. Antennae usually 

 more or less drooping, rarely porrected, and approximated at their 

 base, each consisting of three joints, with a dorsal arista on the 

 third joint; the threc joints vary in Icngth, but the third is usually 

 the longest; the dorsal arista is usually one-jointed and bare in 

 Fgyptian species, although it may be remarkably jolumose in other 

 Paiaearctic groups and is distinctly three-jointed in the genus 

 Eumerus; occasionally this arista may become a terminal style in 

 which case the antennae are conspicuously porrected and elongated 

 {Cerioides). 



Thorax comparatively large and robust, of normal shape, 

 usually dark coloured with three paler, more or Less conspicuous 



