1923] 
Studies in Asilidoe (Diptcra) 
213 
8. Upper plate divided into two long tapering parts ending 
in a knob-like enlargement, with a tooth on inner surface 
and a pencil of yellow hair on outer edge (N. 
Y.; N. Car.) - 6rms Banks 
Upper plate a slender finger-like undivided projection 
about four times as long as wide and with parallel sides, 
lateral arms short and heavy. (Cal.; Wash.) media Banks 
9. Tibiae except tips reddish-yellow; notum heavil}^ coated 
with fulvous, abdomen metallic violaceous; large species, 
11-13 mm 10. 
Only base of tibiae yellowish; mesopleural pollen extending 
down along posterior edge; face of male silvery, of 
female golden; 7-9 mm. (Wash., Id.,; doubtful if East) 
sackeni, form rivalis new 
10. Mesopleural pollen along upper edge only; face of both 
sexes brassy. (Cal., Wash.) nitida Will. 
Meso pleura with dense fulvous pollen and pile extending 
down along posterior edge; face of male silvery. (Cal.) 
doanei, n. sp. 
11. Abdomen wholly black; femora with black line above.. . . 12 . 
Abdomen in part reddish, at least with lateral spot or in- 
cisures reddish; femora wholly yellow; thorax polished 
black 14 . 
12. Mesonotum densely coated with golden pollen; wings 
largely yellow. (Ida., Wash., Or.; if eastern in dis- 
tribution, probably dimorphic form of albius Walk.) 
sackeni Will. 
Mesonotum thinly coated with yellow pollen, leaving two 
narrow black lines 13 . 
13. Face silvery, mystax white; wings hyaline. (Eur.; Mass.) 
hau77ihaueri Mg. 
Face golden, mystax yellow; wings dark. (Cal.) vera Back 
14. Coxae black; abdomen reddish, first four segments more 
or less black; arista one-sixth the third antennal joint; 
wings blackish. (Cal.) ruhida Coq. 
Coxae yellow; style one-fourth to one-half the third an- 
tennal joint; wings lighter; hind metatarsus swollen, 
equal to next three joints in length 15 . 
