DURHAM DIPTERA. 32 1 



XXXVIII. 528. 



5 (6). The whole length of 0.3. distinctly lighter than the 



rest of the wing. ( 2 339- Uneata, Fin.) 



6 (5). 0.3. not lighter than the rest of the wing. 



7 (8). Dorsum orange. (2340. rtifa, Pz.) 



8 (7). Dorsum lead-grey. (2341. cucularia, L.) 



529. Sepedon, Ltr. 



1 (2). Blue-grey species. (2342. sphegeus, F.) 



2 (1). Orange species. (2343. spmipes, Scop.) 



Family XXXIX.— PSILID^E. 



TABLE OP GENERA. 



1 (8). V.I. a. absent or rudimentary. 



2 (7). Antennae shorter than the face, third joint oval or 



round. 



3 (6). Male hind femora neither thickened nor bent. 



4 (5). Face distinctly retreating ; costa unbroken; O.6 1 as 



long as, or only a little shorter than 0.5 1 . 



Psila, Mg. (530) 



5 (4). Face almost perpendicular; costa broken where the 



end of V.I .a. would be were it present; 0.6 1 much 

 shorter than 0.5 1 . Chyliza, Fin. (532) 



6 (3). Male hind femora thickened and bent. 



531. Psilosoma, Ztt. (2355. Itfebvrii, Ztt.) 



7 (2). Antennas longer than the face ; third joint linear. 



Loxocera, Mg. (533) 



8 (1). V.I .a. distinctly present. 



534. Lissa, Mg. (2364. loxocerina, Fin.) 



TABLES OP SPECIES. 



530. Psila, Mg. 



1 (10). Dorsum orange. 



2 (7). Abdomen orange. 



3 (4). Large species, at least 8 mm. 



2344. Psila fimentaria, L. 

 South Durham, 1 ?; Deepdale, 1 $, July, 1901. 



U 



