268 Professor Williston on the 



termination of first vein at some distance before the furcation of 

 the fourth ; prefurca of fourth vein about as long as the posterior 

 branch ; anterior branch strongly curved forward in its anterior 

 portion, as in species of Zijgoneura. Length 2 mm. 



Eigbt specimens. There are not more than one or 

 two joints of the flagellum which are yellow in some 

 specimens ; apparently, also the number of white joints 

 at the tip may be limited to one. The humeri are some- 

 times red. The abdomen, when not drawn out, appears 

 almost wholly black in some specimens. 



Zygoneuea. 



Meigen, Syst. Beschr., vi., oO-t, 1830. 



1. Zijgoneura sciastica, n. sp. (PL VIII., figs. 24, 

 wing ; 24ft, part of antenna.) 



$ . Dark brown, or blackish brown, opaque. Antennae as 

 long as the body, its pubescence in some reflection grey. Legs 

 luteous yellow ; tibias infuscated ; tarsi blackish. Wings nearly 

 hyaline ; neuration as in the figure. Length 1-H mm. 



One specimen. 



SIMULIID^. 



SlMULIUM. 



Latreille, Hist. Nat. Crust, et Ins., xiv., 29 1, 1804. 



1. SiiriuUwm tarsale, n. sp. (PL VIII., figs. 25, 

 wing ; 25a, front tarsus of $ .) 



$ . Abdomen black, the proximal segments opaque, the distal 

 four segments shining. Length 2 mm. 



Front and face black, with a light grey reflection. Antennae 

 yellow ; the distal joints somewhat brownish. Mesonotum deep 

 black ; in front, opaque with a silvery shimmer, and with sparse, 

 short, curly, golden-yellow tomentum ; behind, shining. Pleurte 

 black, whitish pruinose. Abdomen black, the basal segments 

 opaque, the distal four segments somewhat shining, and with a 

 delicate whitish pruiuosity. Legs reddish-yellow ; tarsi black, 

 except that the proximal half of the middle and hind metatarsi 

 light yellow ; first and third joints of the front pair each with two 

 long hairs ; second and third joints of the same pair dihited, the 



