THE DIPTEROUS GENUS DOLICHOPUS IN NORTH AMERICA. 27 



C^. Cilia of the calypters black. 

 D^ Tips of hind tiViae black. 



E*. Tips of hind femora black, at least a little blackened above 107. 



E^. Tips of hind femora wholly yellow 114. 



D2. Hind tibiae without a black tip, at most a little blackened on inner 

 side at tip. 

 E'. Hind tarsi wholly black, or nearly so. 



F'. First antennal joint black, at least on upper edge 149. 



F2. First antennal joint wholly yellow 160. 



E^. Posterior basitarsi largely yellow. 



F'. First antennal joint black, at least above 176. 



F2. First antennal joint wholly yellow. 



G'. Third antennal joint wholly black 192. 



G^. Third antennal joint yellow, at least at base 198 » 



FEMALES. 



1. Femora black, at least one pair mainly black 2. 



Femora yellow, the tips or extreme base may be blackened 71. 



2. All femora and tibiae black, knees may be more or less yellow 3. 



One or more pairs of tibiae, and sometimes also one or two pairs of femora 



mainly yellow or yellowish 24. 



3. Middle tarsi with each joint enlarged and black at tip; first two antennal 



joints yellow with the upper edge black. . .No. 33, appendiculatus, new species. 

 Middle tarsi normal, their joints not noticeably enlarged at tip; antennae 

 wholly black, or with the first joint slightly yellow below 4. 



4. Middle and usually hind femora with two or tliree preapical bristles 5. 



Middle and hind femora each with only one preapical bristle 8. 



5. Lower orbital cilia black 6. 



Lov/er orbital cilia pale '• 



6. Wings with a conspicuous brown apical spot No. 23, argentipes, new species. 



Wings clouded along the veins and usually in front of the third vein, 



No. 17, paluster Melander and Brues. 



7. Third antennal joint nearly orbicular in outline, with the arista inserted at 



upper apical corner, and with a small notch below it; fore tarsi distinctly 



longer than their tibiae No. 4, sordidatus, new species. 



Third antennal joint a little longer than wide, the arista inserted at the middle 

 of upper edge; fore tarsi scarcely longer than their tibiae. 



No. 16, adaequatus, new species. 



8. Cilia of the calypters pale, still they may appear blackish in certain lights. . 9. 

 Cilia of the calypters black H' 



9. Rather large species with the tip of the fifth vein much bent and evanescent 



at tip, which is in a notch of the hind margin of the wing. 



No. 9, nigricmida, new species. 

 Rather small species with the tip of the fifth vein gently arched, and nearly 

 reaching the wing margin, which is scarcely notched 10 



10. The silvery pollen of the face extending widely along the orbits of the front. 



No. 6, squamosus, new species. 

 White pollen of the face not extending above the antennae. 



No. 7, viridis, new species. 



11 . Lower orbital cilia black !-• 



Lower orbital cilia pale 16. 



12. Femora broadly yellow at tips; middle basitarsi with a bristle above. 



No. 19, manicula, new species. 

 Femora wholly black, or nearly so - 1^- 



