SCATOMYZIDJE. 131 



6. One sternopleural bristle. ........ 7 



Two sternopleural bristles. . 9 



Three sternopleural bristles. 10 



7. Eyes nearly twice as high as long; front convex; antennae short, situ- 



ated low down ; pale yellow species. . LEPTOPA Zetterstedt. 



Eyes but little higher than long; antennae as long as the face; oral 



border with a single, anteriorly directed bristle. ... 8 



8. Third antenna! joint broad ; front convex ; arista distinctly plumose ; 



five dorsocentral bristles present; moderate sized, shining yellow 



species. MEGOPHTHALMA Becker. 



Third antennal joint long and slender, arista naked ; four dorsocentral 

 bristles; shining black species. . . MICROPSELAPHA Becker. 



9. Antennae as long as the face, third joint rounded, strongly pubescent; 



four dorsocentral, two scutellar bristles ; hind tibiae with two pairs 

 of exterior bristles; shining black. . HEXAMITOCERA Becker. 

 Antennae long as the face, third joint with a sharp upper corner ; arista 

 geniculate in both sexes ; five dorsocentral, four scutellar bristles ; 

 hind tibiae with three pairs of bristles ; small, grayish dusted species. 



GONATHERUS Rondani. 



10. Male arista distinctly geniculate. ... . . . 11 



Arista geniculate in neither sex. ; 12 



11. Third antennal joint long and broad, with an acute upper angle; arista 



short, bare; four scutellar bristles ; dark gray-dusted, bristly species. 



GONARCTICUS Becker. 



Third antennal joint long and narrow with rounded upper angle; arista 

 finely plumose ; two scutellar bristles ; shining black, bristly species. 



CNEMOPOGON Rondani. 



12. Arista distinctly hairy ; four scutellar bristles; hind tibiae with three 



pairs of exterior bristles. . . '. . ORTHACH/ETA Becker. 



Arista bare ; antennae long, third joint usually angulated above ; two 



scutellar, two pairs of tibial bristles. . AMAUROSOMA Becker. 



13. Eyes circular ; antennae long, rounded at tip ; palpi of usual length 



somewhat broadened distally ; abdomen very short. 



SPATHIPHYLLUS Becker. 



Eyes somewhat elongate; antennas long, angulated at tip; palpi much 

 dilated its whole length ; abdomen not remarkably short. 



PSELAPHOPHILA Becker. 

 HYDROMYZIN^E. 



1. Eyes and head round; thorax with five dorsocentral bristles. . 2 

 Eyes and head oval, higher than long; one dorsocentral bristle; an- 

 tennae short ; abdomen flat ; third and fourth longitudinal veins con- 

 vergent; large, bare grayish dusted species. HYDROMYZA Fallen. 



