8 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.65 



2. Sternopleurum with two strong bristles; arista with very dense short hairs 



above and below Lauxania Latreille. 



Sternopleurum with only one strong bristle; arista long haired above_- 3 



3. Marginal cell of wing very much narrower than submarginal, equally wide 



on its entire length Steganolauxania Frey. 



Marginal cell at its widest part as wide as submarginal, much narrowed 

 from apex of first vein basad Lauxaniella Malloch. 



4. Anterior orbital bristle absent Periscelis Loew. 



Anterior orbital bristle present 5 



5. Anterior orbital bristle directed inward 6 



Anterior orbital bristle directed backward 8 



G. Ocellar bristles minute ; face much swollen, projecting very much beyond 

 eyes in profile ; anterior pair of orbital bristles small, closer together than 

 the upper pair, and situated very distinctly nearer to bases of antennae 



than to upper pair Physogenia Macquart. 



Ocellar bristles long and strong ; face not or but little projecting ; anterior 

 orbital bristles large 7 



7. Anterior orbital bristles strong, situated about midway between bases of 



antennae and upper pair and in line with them ; face glossy, with a dis- 

 tinct rounded central convexity ; third antennal segment slender, longer 



than height of head Pachycerina Macquart. 



Anterior pair of orbital bristles moderately strong, situated very close to 

 upper pair; face not glossy, with a very slight longitudinal convexity or 

 almost flat ; third antennal segment tapered, not as long as height of head, 



Camptoprosopella Hendel. 



8. Either second or third wing-vein with setulose hairs basally 9 



Second and third wing-veins bare 11 



9. Setulae present on base of second vein before furcation of third, 



Xenochaetina Malloch. 

 Setulae present on base of third vein distad of furcation from second— 10 



10. Fore femur with a comb of short black setulae on apical third of antero- 



ventral surface ; pteropleura with some fine black hairs in center, 



Eusapromyza Malloch (European), 

 Fore femur without a comb of setulae as above; pteropleura bare, 



Peplomyza Haliday (European). 



11. Presutural bristle absent ; head longer than high, face much receding below ; 



orbits rather densely covered with minute black hairs at bases of antennae, 



Trigonoraetopus Macquart. 

 Presutural bristle present; head higher than long, the face not much re- 

 ceding below, and the orbits not noticeably haired at bases of an- 

 tennae 12 



12. Sternopleurum with one strong bristle 13 



Sternopleurum with two strong bristles, the anterior one the weaker 14 



13. Frons broader than long, concave in center anteriorly; ocellar bristles 



minute; thorax with three pairs of dorsocentrals and one pair of pree- 



cutellar acrostichals Neogriphoneura Malloch. 



Frons sometimes longer than broad, not concave in center anteriorly ; thorax 

 with two pairs of dorsocentrals Deceia Malloch. 



14. Face decidedly and evenly convex, glossy Caliope Haliday. 



Face flat or not evenly convex, opague or subopaque 15 



15. Intra-alar bristle present ; the small black costal .setulae on wing continued 



beyond apex of second vein but not extending to apex of third, 



Minettia Robineau-Desvtndy. 

 Intra-alar bristle absent IB 



