422 PROCEEDINGS OF THE NATIONAL MUSEUM vol. los 



15. Anepisternum dorsally one-third to one-half yellow; only one developed upper- 



orbital seta albiceps 



Anepisternum dark, dorsally not more than one-fourth yellow; two developed 

 upper-orbitals sphondylii 



16. Head with dorsal upper-orbital shorter than the ventral upper-orbital (fig. 



140), or absent 17 



Head with both upper-orbitals or equal length and strength (fig. 1 66) . .18 



17. Grenovertical plates darkened (fig. 140); intraalar row with six to nine setulae 



anterior to and about five posterior to the transverse suture . . angelicella 

 Grenovertical plates yellow (fig. 141); intraalar row with 10 to 12 setulae an- 

 terior to and about 13 to 15 posterior to the transverse suture . aquilegiana 



18. Acrostichal setae in two to five rows 19 



Acrostichal setae in six to eight rows (see also couplet 33) ilicis 



19. Acrostichal setae in two rows or absent 20 



Acrostichal setae in four or five rows aquilegiana 



20. Mesofacial plate, including subantennal grooves, brown or black . . . .21 

 Mesofacial plate yellow, not more than the subantennal grooves dark ... 23 



21. Eye bare 22 



Eye setulose nigra 



22. Mesonotum without acrostichal setae or with not more than one to four; one 



lower-orbital present (see also couplet 26) atricornis 



Mesonotum with about 14 acrostichals in two rows; three lower-orbitals 

 present aflSnalis 



23. Forecoxa dark, distally yellow 24 



Forecoxa entirely dark 26 



24. Antenna with first and second segments yellowish; a,rista not greatly expanded 



(fig. 166) 25 



Antenna with first and second segments brown or black; arista greatly 

 expanded crassiseta 



25. Head with two strong lower-orbital setae (fig. 166); inner postalar seta 



present subtcnella 



Head with one strong lower-orbital, sometimes with a very small second; 

 inner postalar absent plantaginis 



26. Mesonotum with at least eight acrostichal setae in two rows 27 



Mesonotum without acrostichal setae, or with not more than one to four 



(see also couplet 22) atricornis 



27. Third antennal segment with setulae not longer than the basal diameter of the 



arista (fig. 150) 28 



Third antennal segment with setulae two to three times as long as the basal 

 diameter of the arista (fig. 156) lactuca 



28. Mesonotum with about 15 acrostichal setae; vein Mi+a gently undulating (fig. 



143) atripalpis 



Meonotum with about nine acrostichal setae; vein M1+2 straight (fig. 

 151) dura 



29. Head with both upper-orbital setae of equal length and strength (fig. 159) . 30 

 Head with dorsal upper-orbital shorter than the ventral upper-orbital (fig. 157), 



or absent 39 



30. Antenna dark brown or black; tarsi and tibiae black, brown or dark reddish 



brown 31 



Antenna with first, second, and basal portion of third reddish yellow; tarsi 

 and distal portion of tibiae yellow agromyzina 



