TABLE FOR THE DETERMINATION OF THE GENERA. 11 



TABLE FOR THE DETERMINATION OF THE GENERA. 



, f First antennal joint hairy above. 2 



( First antennal joint glabrous above. 16 



9 / Hypopygiuni disengaged. 3 



' Hypopygiuni more or less imbedded. 14 



„ f First joint of the hind tarsi bristly. 4 



( First joint of tbe hind tarsi not bristly. 5 



f Face descending as far as the inferior angle of the eye. 



. Gen. I. Hygroceleuthus. 



4 { 



| Face not descending as far as the inferior angle of the eye. 



Gen. II. Dolichopcs. 



r ( Palpi of the male unusually large. Gen. XII. Diostracus. 



(. Palpi of tbe male small 6 



( Tbe last portion of the fourth longitudinal vein is parallel, or almost 



fi ] so, to the third longitudinal vein. Gen. III. Gymnopteknus. 



I The last portion of tbe fourth longitudinal vein is distinctly convergent 



towards the third longitudinal vein. 7 



("The end of the fourth longitudinal vein is abruptly, or at least steeply 



,. ! deflected anteriorly. 8 



i The end of the fourth longitudinal vein is only gradually deflected 



[ anteriorly. 9 



' Arista with tbe usual pubescence ; the end of the fourth longitudinal 



vein, beyond the angular flexure, runs in a curve. 



Gen. IV. Pakaclius. 



Arista short-plumose ; the end of the fourth longitudinal vein, beyond 



tbe rounded flexure, runs in a straigbt line. 



Gen. V. Pelastouecrus. 



/ Tbe face reaches down to tbe inferior corner of the eye. 



9 ) Gen. VI. Tachytrechds. 



' The face does not reach down to the inferior corner of the eye. 10 



1n ( Proboscis and palpi very much prolonged. Gen. VII. Orthochile. 



I Proboscis and palpi not prolonged. 11 



,, ( Scutellum hairy. Gen. VIII. Sybistroma. 



( Scutellum not hairy 12 



19 ( Hypopygium sessile. Gen. IX. Hercostomus. 



( Hypopygiuni pedunculated. 13 



,q (Second antennal joint of usual shape. Gen. X. Hypophyllus. 



I Second antennal joint rudimentary. Gen. XI. Haltericebus. 



