332 



SUBFAMILY CHARACTERS 



Larva and Puparium. — Head elongate; antennae distinct but 

 short. Body broad, almost parallel-sided, slightly narrowed anterior- 

 ly, rounded posteriorly, with distinct vittae ; segments distinct ; dorsal 

 segments with a transverse series of 6 strong bristles; lateral mar- 

 gins of each segment except the apical one with 2 bristles; ventral 

 segments with bristles similar to but weaker than dorsal series, 

 spiracular chamber transverse, situated on disc of apical segment near 

 apex ; apical segment with a number of long marginal hairs and a few 

 on disc. 



Imago. — Antennae short, with an apical or dorsal arista; abdomen 

 with 5 or 6 visible segments ; discal cell emitting 3 veins. 



Key to Genera 



larvae 



1. Pale stripes on disc of dorsal segments geniculated on each segment 



Geosargus. 



— Pale stripes on disc of dorsal segments straight Microchrysa. 



Geosargus Bezzi 



This genus is synonymous with Sargus of Aldrich's Catalogue, 

 Sargus Fabricius being preempted by Sargus Walberg. 



GENERIC CHARACTERS 



Larva and Puparium. — The larva differs from that of Micro- 

 chrysa in the shape of the head, which is much shorter in comparison 

 with its width than in that genus. 



Imago. — Brilliant metallic blue or green flies, with slender bodies 

 and unspined scutellum. 



HABITS OF EARVAE 



The larvae are scavengers, feeding on decaying vegetation and 

 manure. 



HABITS OF IMAGINES 



Commonly found on leaves of trees and bushes, especially if in 

 the sunshine, and particularly on such trees or bushes as border pas- 

 tures. 



One species, nubeculosus Zetterstedt, was introduced into North 

 America from Europe. It has been recorded as feeding in the larval 

 stage on decaying turnips and other root-crops. 



