^'ORTII AMERICAN DIPTERA. 16') 



one in discal cell just beyond small crossveln, extending across the third and 

 fourth posterior cells, extreme apex of third posterior, apex of second and first 

 posterior, of the third suhinarjiinal and sometimes also of the second sul)mar- 

 ginal cell ; a spot in outer end of mariiiual cell extending into the second sub- 

 marginal cell, and sometimes united with tlie hyaline at apex of wing; a spot in 

 last third of first submarginal cell ; a small spot in apex of second basal cell, and 

 sometimes one in centre of second sul)inarginal cell ; a subhyaline spot in first 

 basal and base of marginal cell; first sul)marginal cell divided by a crossveln 

 into two cells. Length 10 mm. 



Arizona! Four specimens (Williston, Keen). 



I take great pleasure in naming tliis interesting .species in honor 

 of my young friend, Mr. Eugene L. Keen, of Pliiladelphia, Pa., 

 who has aided me nuicli in my studies of this difficult group. 



4. Anthrax ieiiea n. sp.— Wholly black. Front whitish tomentose and 

 black pilose; face much retreating below, white tomentose : proboscis not pro- 

 jecting beyond epistoma; first two joints of antennse of an equal length, third 

 joint subglobular at its base, the styli form portion .slender and linear; occiput 

 white tomentose. Thorax bronze-colored tomentose, the sides and front end 

 whitish pilose, the dorsum black pilose, bristles of hind angles black; pleura 

 white inlose: scutellum bronze-colored tomento.se, bristles black. Abdomen 

 black tomentose, a white tomentose crossband on bases of second and fourth 

 segments and a crossband of bronze-colored tomentum on bases of third, fifth 

 and following segments, occupying nearly whole dorsum of last three segments; 

 sometimes a similar crossband on second segment ; sides of abdomen quite abun- 

 dant pilose, that on sides of the first segment, basal half of second and fourth, 

 and sides of last two segments white, on sides of rest of abdomen black ; last 

 segment in the male destitute of silvery-white tomentum ; venter white tomen- 

 tose, a crossband of black tomentum on bases of third, fifth, sixth and seventh 

 segments. Legs yellowish or black tomentose, front tibise provided with bris- 

 tles, claws of front tarsi minute. Wiugs hyaline, costal cell yellowish ; ante- 

 costal cell wholly black tomentose. Length 7-8 mm. 



California. Xine specimens. 



5. Anthrax nebiilo n. sp. — Same as mnea except: Legs yellowish ; tomen- 

 tum of front and face, bri.stles of thorax and pile of ])k'ura, largely yellowish. 

 Al)domen, except first segment and base of second, almost wholly bronze-colored 

 tomentose; last segment in the male largely silvery tomentose; front tibise des- 

 titute of bristles. Length 9 mm. 



Wasliington Territory! A single specimen (Williston). 



(J. Aiitlirax «*onse.*».«*or n. sp. —Wholly black. Front yellowish-white 

 tomentose and black pilose; face sligiitly retreating below, j'ellowish-white to- 

 mentose ; proboscis not projecting beyond epistoma; first two joints of antenmv 

 of nearly an equal length, third joint subglobular at its base, the styliform por- 

 tion slender and linear; occijjut white tomentose. Thorax behind golden yel- 

 low tomentose, the dorsum black pilose, sides and front end yellowish pilose, 

 liristles of hind angles reddish; i)leura yellowish pilose; scutellum on hind 

 margin golden yellow tomento.se, the liri.stles black. Abdomen black tomentose. 

 a crossband of yellowish tDmentum on bases of second, third and fourth segments 



