10 (11) Face and scutellum entirely black; 



thorax provided on the sides above 

 the notopleural depression and before 

 the transverse suture with a rather 

 prominent tubercle ; discal cell 

 shorter than the subapical one .... 



11 (10) Face and scutellum yellow; thorax 



without such a prominent tu':ercle 

 on the sides ; discal cell as long as 

 or only a little shorter than the sub- 

 apical one. 



12 (15) Thorax without a sharply defined 



yellow stripe on the sides, or with a 

 very short one, which does not pass 

 the suture ; abdomen usually broad 

 and oval in shape. 



13 (14) Thorax provided in front with a distinct 



collar of hairs ; opening of buccal 

 cavity narrow and linear; ocelli at 

 some distance from the vertex .... 



14 (13) Thorax without a distinct collar ; 



opening of buccal cavity short and 

 oval; ocelli placed near the vertex. . 



15 (12) Thorax with a sharply defined yellow 



notoplenral stripe, which passes the 

 suture and usually reaches the scu- 

 tellum ; abdomen narrow and with 

 parallel ndes. 



16 (17) Abdomen narrower than the thorax, 



not flattened, usually longer than 

 the wings ; male genitalia very large 

 and orbicular 



17 (16) Abdomen as broad as or a little broader 



than the thorax, flattened, shorter 

 than the wings ; male genitalia of 

 smaller size 



18 (5) Abdomen stalked, often tub ulnr; discal 



cell a little shorter than the subapical 

 one ; face tuberculate 



19 (4) Face with a very prominent snout- 



like projection below ; third vein 

 curved backwards and ending be- 

 yond tip of wing ; first and second 

 veins very long 



20 (3) Third antennal joint linear, very elon- 



gate, many times longer than the 

 iirst two joints together ; subapical 

 and posterior cross-veins recurrent ; 

 vena spuria wanting; thorax and 

 scutellum provided with macro - 

 cheetre : eyes of male separated .... 



21 (2) Small cross-vein near or beyond the 



middle of the discal cell. 



22 (39) Third vein with a deep sudden down- 



wardly directed kink about middle 

 of the subapical cell. 



MELANOSTOMA, p. 18. 



ASARCINA, p. 21. 

 SYHPHUS, p. 29. 



SPH^ROPHOIUA, p. 35. 



XANTHOGRAMMA, p. 36. 

 BACCHA, p. 38. 



RHINGIA, p. 50. 

 GRAPTOMYZA, p. 55. 



