184 DIPTERA OF NORTH AMERICA. [PART IV. 



second, and nearer to the former than to the latter. (Compare 

 the figures of the wings of the European species nubila smdjiava 

 in SchummeVs Beitrage, etc. Tab. II, fig. 4 and 5, which, in 

 regard to the position of the cross-vein, are in perfect agreement 

 with the American species.) 2. The auxiliary vein is longer than 

 in Goniomyia, that is, it extends beyond the origin of the second 

 longitudinal vein to a distance which is equal to half the breadth 

 of the wing, or a little shorter; the cross-vein is very near its 

 tip (this, according to the same figures of Schummel, is also the 

 case with the European species). 3. Whenever the discal cell is 

 open, it coalesces with the second, not with the third posterior 

 cell (the latter is the case in Goniomyia) ; in other words, it is not 

 the anterior branch of the fourth longitudinal vein, but the 

 posterior one, which is forked (this again is distinctly mentioned 

 by Schiner, 1, c. p. 544, lines 4 and 14 from the bottom, for the 

 European species, and figured by Schummel). 4. The forceps 

 of the male has a different structure ; I am unable to describe it, 

 not having observed it on any living specimen, but even dry ones 

 show plainly that the forceps has a more simple structure, and 

 none of the numerous branches which distinguish the forceps of 

 Goniomyia. 



Besides the single North American species, described below, 

 three European species undoubtedly belong here : Limnobia 

 diluta Zett. (Schiner) ; Limn, fiava Schum. ; Limn, nubila 

 Schum. 



The name of this new genus is derived from I^fSoj, steady, 

 unshaken. 



Description of the species. 



1. E. stigmatica, n. sp. % . — Fuscana, halteribus pallidis, alis im- 

 maculatis ; cellula discoidalis aperta, cum secunda posteriori confluens. 



Brownish, with pale halteres, immaculate wings, and an open discal cell 

 coalescent with the second posterior cell. Long. corp. 0.2. 



Dull brownish ; antennae black ; in the male, with rather long 

 verticils ; a sulphur yellow spot on the humeri ; halteres pale 

 yellow ; forceps of the male reddish-brown ; feet tawny. Wings 

 nearly hyaline ; veins brown ; stigma very slightly tinged with 

 brown ; the tip of the auxiliary vein is nearly in the middle of the 

 distance between the origin of the prsefurca and the marginal 

 cross-vein ; the distance between the tip of the first longitudinal 



