AMERICAN DIPTERA. 363 



I have before me several specimens from southern Georgia which I 

 take to be rufescens Macquart. They resemble somewhat the females 

 of discolor, but run larger and are stouter; the thoracic dorsum does 

 not show the two very narrow median black stripes unaccompanied 

 by black lateral stripes, which is characteristic of the dorsum of dis- 

 color females; and the black of the abdomen, which in discolor is 

 confined to the anterior half of the lateral margins of the segments, 

 on these specimens extends upward and often meets on the tergum 

 to form a blackish cross-band. A description of these specimens is 

 as follows: — 



% 9 • — Length 18—25 mm. — Yellowish-brown; dorsum of thorax 

 with brownish to velvety-black stripes; the lateral and posterior mar- 

 gins of the abdominal segments narrowly, and the posterior angles 

 more broadly, pale golden pruinose, the rest of each segment reddish 

 except broadly on the lateral margins where it is blackish; this black 

 of the sides extends upward upon the tergum thus giving the abdomen, 

 as a whole, a blackish appearance. 



Face, front, occiput, thorax except dorsal stripes, and the coxae, 

 pale golden pruinose; bristles of mystax and scattering hair of face just 

 above whitish ; palpi and antennas reddish, the former with yellowish, 

 the latter with black, hair. Bristles of occiput, coxae, first segment of 

 abdomen and before the halteres pale ; of the thoracic dorsum and 

 scutellum black. The three dorsal stripes reddish-brown, the median 

 stripe very narrowly divided by a longitudinal pale line, and the lateral 

 stripes as usual, bisected at the transverse suture; the stripes vary 

 from wholly reddish-brown with traces of black along their middle, to 

 wholly velvety black, and in the blackest the median stripe is but 

 very faintly divided. 



Abdomen quite stout, the lateral and posterior margins of the seg- 

 ments, narrowly, and the posterior angles more broadly, pale golden 

 pruinose; the anterior margins sometimes narrowly likewise pruinose; 

 last two segments of female polished. The anterior lateral margins 

 of segments 2-5 black; this black in some specimens soon shades off 

 into a rich reddish-brown on the middle of the tergum or, as in others, 

 it may extend upward on either side to meet across the tergum, thus 

 giving the abdomen a blackish appearance, broken only by the golden 

 bloom. Genitalia of male reddish with pale pile. Legs brownish- 

 yellow, hair and bristles black, tips of tibiae and tarsi black. Halteres 

 fuscous. Wings wholly yellowish hyaline. 



Habitat. — Macquart records this species from Philadelphia, 

 but his specimens may have come from one of several places 

 in this country. Van der Wulp identified this species from 

 Arizona, but my specimens belong to the National Museum 

 and were collected in Georgia. 



TRANS. AM. ENT. SOC, XXXV. SEPTEMBER, 1909 



