GEOMYZIDAE — DROSOPHILIDAE. 45 



joint of the antennae being nnguicnlate. The Hydrellina and 

 Ephydrina, in which that joint is not unguiculated, differ from 

 each other by the former having the eyes hairy and the latter 

 bare. 



The N. A. species hitherto recorded have been so badly charac- 

 terized that there is no possibility to decide to which section, and 

 of course far less to which genus they belong. The species which 

 I am acquainted with and have described in the following pages, 

 are distributed among the three above named sections as follows: 



1. Notiphilina: 1. Dichjeta Meig. with two European species; 



2. Kotiphila Fall, five species ; 3. Paralimna Loew, one species ; 

 4. Psilopa Fall, five species ; 5. Discocerina Macq. five species. 

 II. Hydrellina: 6. Hydrellia Desv. six species; 7. Philygria 

 Stenh. three species. III. Ephydrina: 8. Ochthera Latr. four 

 species, one of which is identical with a European species; 9. 

 Brachydeutera Loew, one species ; 10. Parydra Stenh. two 

 species; 11. Ephydra Fall, one species; 12. Scatella Desv. 

 three species, one of which cannot be positively distinguished as 

 yet from a European species. 



Fam. LIY. GEOMYZIDAE. 



Charact. — Front with, stout bristles above; border of the mouth with vi- 

 brissas. Clvpeus rudimentary. Middle tibiae with spurs ; all the 

 tibiae with a small erect hair on the exterior side before the tip. 

 Wings with bristles on the costa ; first longitudinal vein exceed- 

 ingly abbreviated, and the auxiliary vein so approximated to it 

 that it is distinctly separated from it only towards the base ; the 

 two posterior basal cells very small. 



I know only one species of this family indigenous in N. A. and 

 belonging to the genus Diastata. Mr. Walker records an insect 

 which he believes to be likewise a Diastata. 



Fam. LY. DROSOPHILIDAE. 



Charact. — Front with bristles above ; face with distinct sub-antennal fur- 

 rows ; at the border of the mouth there is a feeble, frequently rather 

 indistinct small vibrissa. Middle tibiae with very feeble spurs ; on 

 the exterior side of the tibiae there is either a very small or no erect 

 bristle before the tip. Wings without bristles on the costa ; the 



