214 DIPTERA OF NORTH AMERICA. [PART IV. 



Front grayish ; palpi infuscated ; rostrum yellowish ; antenna 

 brown ; basis of the third joint pale ; joints of the flagelluni 

 elongated-elliptical ; verticils moderate. Thorax brownish-yel- 

 low with two pale brown stripes, which become paler* near the 

 collare, where they communicate with a brown spot near the 

 humerus ; they extend beyond the suture posteriorly ; pleurae 

 pale, sometimes with a pale brown stripe ; halteres pale, slightly 

 infuscated ; feet pale tawny, tips slightly infuscated. Abdomen 

 brownish ; ovipositor arcuated, of moderate length. Wings 

 slightly tinged with grayish ; stigma faintly infuscated ; marginal 

 cross-vein at the tip of the first longitudinal vein ; pragfurca gently 

 arcuated, rather short, not longer than the petiole of the first sub- 

 marginal cell ; this petiole is conspicuously arcuated ; the branches 

 of the second vein are nearly parallel, except at the basis ; the 

 second submarginal cell is only a trifle longer than the first pos- 

 terior ; the second posterior cell rather long, in comparison to its 

 petiole (the relation between them is variable) ; the great cross- 

 vein is usually opposite the middle of the discal cell. 



Hah. Trenton Falls, N". Y. 



This species is easily distinguished by the arcuated petiole 

 of its first submarginal cell. 



11. Li. areolata 0. S. % aud J. — Ocliracea ; alse suLhyalin®, im- 

 maculatse ; cellula discoidali elougata ; ejus augulus interior et pn-e- 

 furcfe initium ab aljB basi fere seque distantes ; cellulse submargiiialis 

 secunda et posterior prima longissimjB ; prjefurca brevis. 



Ochraceous ; wiugs subhyaline, immaculate ; discal cell elongated ; its 

 inner end not much more distant from tlie basis of the wing than the 

 origin of the prsefurca ; the second submarginal and the first posterior 

 cells are very long ; prsefurca short. Long. corp. 0.27 — 0.32. 



Syn. Limnophila areolata 0. Sacken, Proc. Ac. Nat. Sc. Phil. 1859, p. 237. 



Ochraceous yellow, antennae, except the basal joint, slightly 

 infuscated ; front sometimes with a yellowish-gray bloom ; knob 

 of the halteres more or less infuscated ; abdomen brownish above, 

 venter pale ; forceps ochraceous ; ovipositor long, slender, very 

 slightly curved ; feet yellowish, the latter part of the tibiae and 

 the tarsi, except at the basis, brownish ; sometimes the tibije are 

 altogether yellowish. The antennae, if bent backwards, would 

 not reach much beyond the root of the wings ; the joints of the 

 flagellum are about twice longer than broad, gradually becoming 



