14 BULLETIN 116, UNITED STATES NATIONAL MUSEUM. 



27. Hind tibiae yellow with black tips (New York)... No. 41, nequalis, new species. 

 Hind tibiae mostly black (New Yoak) No. 26^, hurnesi, new species. 



28. Distance between the third and fourth veins at tips only a little more than half 



as great as at the bend in the last section of fourth vein (Oregon; Washington) 



No. 35, convergens Aldrich. 



The third and fourth veins approach each other but little beyond the bend of 



fourth vein 29. 



29. Hypopygial lamellae with very dense black hair on apical portion (Eastern 



Canada; North Dakota) No. 37, barbicauda, new species. 



Lamellae with only the usual fringe of bristles and hairs 30. 



30. Costa distinctly enlarged at tip of first vein, gradually tapering to its tip (Sas- 



katchewan) No. 34, fumosus, new species. 



Costa with a very small knotlike enlargement at tip of first vein (New York). 

 ' No. 26^, hurnesi, new species. 



Costa not distinctly enlarged at tip of first vein; only one or two of the lower 

 orbital cilia yellow; fore tarsi slightly compressed at tip (New York). 



No. 41, aequalis, new species. 

 Group E. 



1. Arista ending in a lamella (New Hampshire) No. 88, dorycerus Loew. 



Arista plain 2. 



2. Anterior tarsi plain 3 



Fore tarsi ornamented 7. 



3. Anterior tibiae with a fringe of very long black hair on the front surface (Nevada). 



No. 84, bnrbipes, new species. 

 Anterior tibiae without such hair 4. 



4. Wings with a conspicuous brown cloud on costal margin near the apex^ Massa- 



(chusetts) No. 87, omatipennis, new species. 



Wings with a brown cloud 5. 



5. First two joints of the antennae yellow below, the first large (Vancouver Island; 



Puget Sound) No. 161, bruesi, new name. 



Antennae wholly black, first joint small as usual 6. 



6. Middle and hind femora ciliated below (Wisconsin ; Europe) 



No. 83, ungulatus Linnaeus. 

 Femora without cilia below (Alaska, Europe) No. 68, rupestris Hall. 



7. Hind femora without cilia below (Northwest Territory). .No. 86, daysyops Malloch. 

 Hind femora with cilia below 8. 



8. Cilia of hind femora yellow; fifth joint of fore tarsi much longer than fourth 



(Hudson Bay Territory; Europe) No. 85, brevipennis Meigen. 



Cilia of hind femora black; fourth and fifth joints of fore tarsi nearly equal in 

 length (Eastern States) No. 82, pachycnemus Loew . 



Group F. 



1. Arista enlarged at tip (Labrador) No. 116, pilatus, new species. 



Arista plain 2. 



2. Antennae black, the first and second joints may be yellow^,below 3. 



First antennal joint wholly yellow 31. 



3. Fore coxae blackened at base for more than half their length, at least on outer 



surface 4 . 



Fore coxae yellow, sometimes with a black or green stripe or spot on outer 

 surface 5. 



4. Hind femora blackened at tip; fore tarsi plain (Puget Sound). 



No. &9,fucatus, new species. 

 Hind femora wholly yellow; fore tarsi ornamented (mdespread). 



No. 138, longimanus Tocav 



