AGROMYZIM 



295 



5. Posterior cross-vein opposite or before the anterior cross-vein, that 



is the second basal and distal cells together are but little longer 



or shorter than the first basal cell. . . Napomyza. 



Posterior cross-vein at least its own length beyond the anterior 



cross-vein. .......... 6 



6. The third antennal joint terminates in a spiny point (9, 1O) . 



Ceratomyza. 

 Third antennal joint not terminating in a spiny point. . 7 



7. Third antennal joint rounded, of moderate size. . . 8 

 Third antennal joint very large, subquadrate (3). Phyllomyza. 



8. Arista wholly wanting; second basal and discal cells confluent. 



Cryptocheetum. 

 Arista present. ....... 9 



9. Proboscis long and geniculate. ..... 10 



Proboscis short and not geniculate. . . . . .11 



10. Front long and plane, or concave, longitudinally (4, 5). 



Platophrymyia.f 

 Front shorter and convex (14). . . . Desmometopa. 



11. Vibrissse distinct!}" above oral margin; face strongly convex. 



Hemeromyia. 

 Yibrissae not distinctly above the oral margin (6, 7, 8, 2O). 



Agromyza. 

 No distinct vibrissae (see Ephydridse, (25,36). . Pelomyia. 



12. Second basal cell united with the discal cell; first basal cell but 



little longer than the anal (1,2). . . Aulacigaster. 

 Discal cell separated from the second basal. . . . -13 



13. Oral vibrissae present (Milichinse). ..... 14 



Oral vibrissae wanting; postvertical bristles convergent; auxiliary 



vein usually distinct from first longitudinal through a consider- 

 able part of its course (Ochthiphilinse) . .... 21 



14. Costa with a distinct incision before the tip of the first vein. 15 

 Costa not with such incision. ...... 16 



15. First posterior cell narrowed in the margin; posterior orbits with 



a distinct incision (1112). . . . Ophthalmomyia. 



First posterior cell not narrowed in the margin; posterior orbits 



not incised (19) Milichia. 



t I am not sure of the distinction of this genus from Desmometopa. 



