384 DURHAM DIPTERA. 



LVII. 



are also often present. The arrangement in the different 

 genera may in a general diagrammatic form be represented 

 thus : — 



. ... .... .... .... .... — Vertical row. 



oc oc oc oc oc — Ocelli. 



> Frontal rows. 



• J 



Post-antennal 

 Phora. Trineura. Conicera. Gymnophora. Metopina. [row. 



The bristles noted on the tibiae are in addition to the one 

 or two or more terminal spurs beneath. 



TABLE OF GENERA. 



1 (2). Flat, broad species ; frons, thorax, legs, and costa 



bare ; V.3. forked. 



660. Platyphora, Verr. (2837. lubbocki, Verr.) 



2 (1). Body of the usual arched shape. 



3 (4). Footpads and empodium absent; only three thin- 



veins present ; frontal bristles absent ; eight short 



fronto-orbital bristles present. 



664. Metopina, Mcq. (2874. galeata, Hal.) 



4 (3). Footpads and empodium distinctly present. 



5 (6). Frons without bristles; costa only fine-haired, not 



bristly. 



661. Gymnophora, Mcq. (2838. arcuata, Mg.) 



6 (5). Frons with strong bristles ; costa with bristly ciliation. 



7 (8). Post-antennal and lower frontal bristles absent ; 



present, in addition to the vertical row, three 



fronto-orbital bristles on each side, and one pair of 



upper frontal bristles ; eyes bare ; mid tibiae with a 



row of outer bristles ; V.3. not forked. 



Trineura, Mg. (662) 



8 (7). Post-antennal bristles generally present ; not more than 



two fronto-orbital bristles on each side ; eyes hairy. 



9 (10). Arista terminal ; antennae short in the female, but 



very long and pear-shaped in the male ; only two 



horizontal rows of head bristles, the vertical and 



the upper frontal, in addition to the post-antennal. 



Conicera, Mg. (659) 



