314 DURHAM DIPTERA. 



XXXVI. 511. 



19 (18). Costa thinly spined. {variabilis, Lw.) 



20 (17). Pleurae grey. 



21 (22). Femora not thickened. {cineraria, Lw.) 



22 (21). Femora thickened. 



23 (24). Colour black-grey. {crassipes, Lw.) 



24 (23). Colour light grey. {pt/silla, Lw.) 



512. Heteromyza, Fin. 

 From Collin's table of species in E.M.M., 1901. 



1 (4). Praesutural bristles present on the thorax; antennas 



entirely black; fronto-orbital bristles present in 

 both sexes. 



2 (3). Male frons with a greyish white vertex and side lines, 



and very wide behind ; face narrower than frons in 

 both sexes. (2278. atricornis, Mg.) 



3 (2). Male frons all dull red and much narrower than 



preceding; face wider, or not narrower than the 

 frons in both sexes. ( 22 79- commixta, Coll.) 



4 (1). Praesutural bristles absent ; antennae reddish brown ; 



fronto-orbital bristles absent in the male, the frons 

 being narrower behind than at the antennae. 



(2280. oadata, Fin.) 



513. Tephrochlamys, Lw. 



1 (2). Second antennal joint much thickened at its base. 



{tarsalis, Ztt.) 



2 (1). Second antennal joint not thickened at its base. 



3 (4). Stigma distinctly darkened at its base; the third 



antennal joint orange. (2282. flavipes, Ztt.) 



4 (3). Stigma not darkened at its base ; third antennal joint 



black. 



5 (6). First and second antennal joints brown. 



2281. Tephrochlamys rufiventris, Mg. 

 Common. Bishop Auckland, 1 $ and 12 $, March- 

 August, 1898-1900. 



6 (5). First and second antennal joints yellow, {laeta, Mg.) 



