NOKTII A.MiniHAN Dll'TKHA. 59 



12. First posterior cell imicli narrowed in tlie margin. Mickofezii).* 

 First posterior cell but little or not at all narrowed in the margin. 



Si: PS ID.*; 



13. Hind metatarsi shorter than the following joint and much thick- 



ened Bokborida: 



Hind metatarsi longer than the following joint and not more 

 thickened. ......... 14 



14. Second basal cell united with the discal cell ; posterior cross- 



vein present, ^y^^pt "> t\Uroy^*.u.r3^ ... 16 



Second basal and discal cells distinct, or, if united, the posterior 



cross-veins wanting. 18 



15. Legs long and slender ; alxlomen elongate and narrow. 



MiCUOPEZID/K 



Legs moderately long and usually rather strong; abdomen ovate, 

 or elongate elliptical . 16 



16. Front without bristles, or, at most, bristly at the top ; third joint 



of antennaj rounded, or, if elongate, the head triangular in 



profile. OsciNiD.i; 



Front bristly at least as far as the middle ; third antennal joint 

 elongate, oval, or rounded; head not triangular in profile. 17 



17. Face large; mouth opening large; anal cell wanting. 



EPHVDRIDiK 



Face not lar-ge and arched ; anal cell present. DROSopiiiLiDifi AnlvcJjj-it'T'. 



18. Oral vibrisste present. 19 



No vibrissfe on oral margin 22 



19. Front bristly at the vertex only, or not at all. . . Sepsid.e ''yryJL'\AiJU\ 

 Front bristly at least as far as the middle. ... 20 



20. Posterior cross-vein before the middle of the wing, approxi- 



mated to the anterior cross-vein. . . AgROMYZID.iB v,o fv* J.[.'«v.\ t.'H»x I 

 Posterior cross-vein at or beyond the middle of the wing, some- 

 times absent 21»Ky\\t-»"Sii *''*«*» 



21. Arista long plumose or pectinated. AsTEin.*:, Drosophilida: 

 Arista shortly and thickly plumose, or pubescent, or bare, 



wi'r- pr(ift(i.\ tl^''.^''- L(. ■/'!«; - - _ Geomyzida; 



22. Anal cell of considerable size and distinct. ... 23 

 Anal cell small and indistinct 24t 



23. Front bristly Trypetid^ 



Front bare, or bristly at tfie vertex only. Psiud.* 



