AMERICAN DIPTERA. ' 359 



(^. — The female differs from the male most noticeably in that the 

 abdomen is yellowish or brownish-red, and that on the anterior lateral 

 margins of segments 2-5 in front of the white bloom is a black spot, 

 sometimes indistinct. The trichostical bristles are only in exceptional 

 cases yellow; but the bristles of the occiput are usually yellow and 

 the dorsal stripes paler. 



Type.—M. C. Z. 



Habitat. — Mass., Conn., N. Y. (Long Island); N. J. (Aug. 

 26, E. Daecke) ; Caldwell and Merchantville (July 19, Smith 

 Cat.); Pa. (Delaware Co., C. W. Johnson, Aug. 17 27) ; Del.; 

 Washington, D. C. (Aug. 22, J. C. B rid well) ; Md. (June). 



Described from twenty males and fifteen females. There 

 are sixteen specimens at the M. C. Z. The male of this species 

 is most easily recognized by the very slender, long, black ab- 

 domen, with the white bloom on the lateral margins and 

 posterior angles of the segments. In greased specimens these 

 silvery white areas appear reddish. The female is less easily 

 recognized from bilineata and symmacha, but, so far as I know, 

 is quite unique in always possessing the two very narrow and 

 narrowly separated velvety black stripes, reaching backward 

 hardly beyond the transverse suture. In one female the dor- 

 sum, aside from the stripes, is nearly olivaceous. These two 

 median stripes are characteristic in the male, but in some 

 cases one finds the broader lateral stripes, which ordinarily 

 are reddish, of a deep velvety black. 



I have no account of this species farther south than North 

 Carolina. The type females of bilineata are very close to the 

 females of discolor (see note under bilineata). Dasypogon 

 basalts Walker, is, I believe, a female discolor; I do not believe 

 that it is umbrina. 



Deromyia liypomelas. 



Diogmites liypomelas Loew, Cent., VII, 42, 1866. 



9. — Length 17.6-20.5 mm. — Translation. — Reddish-yellow, opaque; 

 stripes of the thoracic dorsum, lateral spots of abdomen, apex and 

 venter black; pile and bristles of entire body pale. 



Reddish-yellow, opaque; pile and bristles of entire body pale. Head 

 golden pruinose. Antennas reddish-yellow, the third segment broader 

 than in most species. Palpi reddish-yellow. Thoracic dorsum thinly 

 covered with pale golden bloom, having three black stripes, the median 

 one divided, the lateral ones very greatly abbreviated anteriorly. 



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



