126 Bulletin of the Brooklyn Entomological Society Vol. XVI 



this group it is not sharply definable on external characters. 

 It is necessary to use the characters given in the table in order 

 tO' retain Arctophila flagrans in the genus ; should the loop in 

 the third vein be considered of prime importance this species 

 would have to be placed in the Eristalinse and a new genus 

 would have tO' be erected. Obviously this would be an error. 



Table of Genera of Sericomyin^. 



1. Short pilose species; abdomen with bright yellow mark- 



ings 2. 



Long pilose species; no yellow ground markings on abdo- 

 men 3. 



2. Post alar callus and margin of scutellum with rather short, 



stout bristles ; third vein with a deep loop into discal cell. 



Condidea. 



Thorax without bristles; third vein at most with only a 



gentle downward curve Sericomyia. 



3. Thorax and abdomen with more or less yellow pile; face not 



unusually broad or swollen Arctophila. 



Pile entirely brownish ; face unusually broad and swollen. 



Pyritis. 

 VOLUCELLIN^. 



Another character of the Volucellinse which may be well to 

 note is the condition of the anterior corners of the abdomen due 

 to the unusual broadness of the squamae. The squamae extend 

 posteriorly as far as the second tergite. Below the squamae the 

 first tergite is greatly depressed, sometimes forming a trench- 

 like groove, and at the same time this area is either bare or 

 possesses pile much shorter than on the posterior corners of 

 the second tergite. This character is also present in several 

 genera of the Eristalinse and may be seen to good advantage 

 in Mallota and Meromacrus. It may be of value to further 

 divide genera and species in these subfamilies. 



Table of Genera of Volucellin^. 



I. Arista very densely plumose, appearing as a solid mass, the 



arista itself thickened Copestylum. 



Arista loosely plumose 2. 



