DURHAM DIPTERA. 39 1 



LVII. 663. 



87 (88). Abdomen yellow, matt-brown above ; frons grey ; 



third antennal joint round ; costa long haired. 



(2860. ftygmcea, Ztt.) 



88 (87). Abdomen yellow, segments 2-4 matt-black ; frons 



yellow in front ; third antennal joint longish ; costa 

 short haired. (2861. fasctata, Fin.) 



89 (86). Costa extending to the wing middle or beyond. 



90 (91). A long and broad brown stigma, almost filling 0.1. 



{costalis, v. Ros.) 



91 (90). No such stigma. 



92 (96). Four scutellar bristles. 



93 (HI). V.4. bent in a single curve, or nearly straight, not 



bent back at the tip. 



94 (95). Costa shortly and finely ciliated ; abdomen yellow, 



with segments 4-6 with black interrupted fore 

 marginal bands. 



Phora picta, Lehm. 

 Hesleden, 1 ?, 1-8-02. 



95 (94). Costal ciliation moderately long ; abdomen all matt- 



black, (ruficornis, Mg., see below, no). 



96 (92). Two scutellar bristles. 



97 (98). Costa with very short ciliation ; abdomen brown 



above; C 1 and C 2 equal. (2868. flava, Fin.) 



98 (97). Costa with long ciliation ; C 1 half as long again as C 2 . 



99 (100). Hind tibiae without strong bristles ; costal ciliation 



moderately long; abdomen varies from matt-yellow 

 to all dark above; 2 mm. (2862. lutea, Mg.) 



100 (99). Hind tibiae with strong bristles ; abdomen yellow, 



segments 3-5 with black hind margins, 3 and 4 

 short in the male. (2863. melanocephala, v. Ros.) 



101 (85). Thorax entirely black, or only partly orange. 



102 (128). Halteres yellow or yellowish brown. 



103 (114). Four equally strong scutellar bristles. 



104 (105). V.3. much dilated ; third antennal joint large and 



yellow ; humeri orange. (aibitalis, Beck.) 



105 (104). V.3. not unusually dilated. 



