DURHAM DIPTERA. 29 1 



XXXIV. 



10 (7). Arista bare ; costa only slightly haired ; V.3. dis- 



tinctly bent at X.4. Scoliaphleps, Beck, {tistulaia, 

 TAX., with four scutellar bristles, and melanacra, 

 Lw., with six scutellar bristles). 



11 (6). Third antennal joint as long as the face; second joint 



not cap-like over the third ; arista not thickened at 

 the base, long, thinly and short haired to the tip ; 

 shining black species. 



Phrosia, Dsv. (albilabris, F.) 



12 (5). Palpi without a long end bristle ; from one to three 



sternopleural bristles. 



13 (20) (23). Three sternopleural bristles. 



14 (17). Arista of the male distinctly bent over, kneed. 



15 (16). Third antennal joint long and thin with rounded 



upper corner ; arista fine haired ; two scutellar 

 bristles ; black shining very bristly species. 



487. Cnemopogon, Rnd. (2206. apicalis, Mg.) 



16 (15). Third antennal joint long and broad with pointed 



upper corner ; arista short and bare ; four scutellar 

 bristles ; dark grey bristly species, not shining. 

 Gonarcticus, Beck, (antennatus, Ztt., with oval 

 eyes and a grey abdomen, abdominalis, Ztt., with 

 quite round eyes and a yellow abdomen). 



17 (14). In neither sex is the arista bent. 



18 (19). Arista distinctly haired ; five dorso-central and four 



scutellar bristles ; mouth bristles distinct ; hind 

 tibiae with three pairs of bristles on the outer side ; 

 mid sized species, thickly dusted with light grey. 

 Orthacheta, Beck, (pilosa, Ztt.) 



19 (18). Arista bare ; antennae long ; third joint usually with a 



sharp upper corner; five dorso-central and two 

 scutellar bristles; mouth bristles distinct; hind 

 tibiae with two pairs of bristles on the outside; 

 slender blackish species, more or less dusted. 



Amaurosoma, Beck. (489) 



20 (13) (23). Two sternopleural bristles, 



