GNOPHOMYIA. 175 



The whole body, including the halteres, of a deep, opaque 

 black ; velvet black on the thorax. Wings smoky, nearly black ; 

 costal cell still darker ; stigma hardly distinct ; a short, almost 

 microscopic pubescence in the apical portion of the wings ; the 

 venation is somewhat different from that of the following species ; 

 the anterior branch of the second longitudinal vein is almost im- 

 perceptibly arcuated ; the posterior branch and the third vein 

 are quite straight ; the petiole of the first submarginal cell (that 

 is, the distance between its inner end and the tip of the praefurca) 

 is not much longer than the distance between the tip of the 

 praefurca and the small cross-vein. The forceps of the male is 

 hairy ; the horny appendages seem to be somewhat stouter than 

 in the following species ; the joints of the flagellum, at least the 

 four or five basal ones, are short, not much longer than broad, 

 with a delicate, short pubescence on the under side. 



Hab. Florida ; I caught a single male, in March, 1858. That 

 Mr. Walker's L. nigricola has been published later than 1859, 

 appears from the circumstance that Mr. Bellardi's work, published 

 in that year, is quoted by him in the same paper (page 2d). 



2. G. tristissima 0. S. % and £ . — Nigra, pedibus piceis ; halteres 

 capitulis flavis ; alee subhyalinae, stigmate oblongo, obscuro. 



Black, feet blackish-brown ; knob of the halteres yellow ; wings subhya- 

 line, stigma oblong, dark. Long. corp. 0.25 — 0.35. 



Syn. Gnophomyia tristissima 0. Sacken, Proc. Ac. Nat. Sc. Phil. 1859, p. 224. 



Body black, but little shining ; mesonotum more gibbose than 

 in G. luctuosa ; a slight hoary reflection on the lower part of the 

 pleurae and sometimes on the front ; feet dark brown, coxae black; 

 stem of the halteres brown, knob yellow ; wings (Tab. II, fig. 5) 

 slightly tinged with brownish-gray ; stigma blackish, elongated, 

 divided longitudinally in two halves by the first longitudinal 

 vein; the marginal cross-vein, usually placed at the inner end 

 of the first submarginal cell, is sometimes a little posterior to it ; 

 both branches of the second longitudinal vein and the third vein 

 are arcuated ; the petiole of the first submarginal cell is longer 

 here than in G. luctuosa ; whereas the small cross-vein is close 

 by the origin of the third vein. The forceps (Tab. IY, fig. 19) 

 and the ovipositor (fig. 19 a) have been described above. 



Not rare ; Washington, D. C. ; New York ; Yirginia ; Upper 

 Wisconsin River (Kennicott). 



