314 ERNEST A. BACK 



dency for the mystax to be almost wholly black, or white and 

 black mixed, and the wings do not seem to be quite so clear. 

 In badly greased specimens the white pruinose spots of the 

 dorsum show only faintly. 



The writer has seen this species resting upon the dead twigs 

 of the sweet fern (Myrica asplenifolia) from which it would 

 dart after its prey. 



Holopogon lautus. 



Holopogon lautus Coq., Jour. N. Y. Ent. Soc, XII, 33, 1904. 

 "cf. — Length 6 mm. — An unusually broad, robust species. Black; 

 the halteres yellow, their bases brownish; hairs and bristles white or 

 yellowish; hairs of mesonotum except posteriorly, very short and 

 sparse. Head gray pruinose; hairs of mystax very sparse, the bristles 

 confined to two or three rows along the oral margin; first two segments 

 of antennae subequal in length, together about three-fourths as long 

 as the third, the latter slightly longer than the slender style. Thorax 

 and scutellum opaque, grayish pruinose; mesonotum with three con- 

 fluent brownish-black stripes, abbreviated posteriorly, and the outer 

 pair much abbreviated anteriorly. Abdomen somewhat polished. 

 Hind legs considerably thickened, the tibiae on the outer and inner 

 sides and the first tarsal segment both above and below quite densely 

 fringed with rather short hairs. Wings from base to beyond apex of 

 discal cell dark brown, the limits of this color strongly arcuate, the 

 remainder of the wing hyaline; apex of second vein before middle of 

 second submarginal cell; wings very broad, the alulae quite strongly 

 developed." 



Type. — A single male specimen in the collection of the 

 Brooklyn Institute of Arts and Sciences. 



Habitat. — Texas. 



I have not seen this species. In wing colorization it must 

 closely resemble atripennis . 



Holopogon nitidiventris. 



Holopogon nitidiventris Bigot, Annales, 1878, 437. 

 2 . — Length 7 mm. — Translation. — In all respects like H. tenerum 

 (see remarks) , excepting thorax is covered with a reddish bloom, lateral 

 margins of dorsum grayish; halteres of a clear testaceous; hair of coxae 

 and femora deeper; abdomen gray, each segment adorned behind with 

 a large triangular spot and on each spot marked with a rounded point 

 of polished black; tarsi somewhat brownish; wings quite clear, of a 

 brownish tinge, which is more marked and intense along the trans- 

 verse veins, the longitudinal veins at base of wing deep testaceous. 



