LIMNOBIA. 89 



furca ; tlie third, double spot, at the tip of the auxiliary vein and 

 at the inner end of the submarginal cell ; the fourth, ring-like one, 

 at the tip of the first longitudinal vein ; cross-veins iufuscated ; 

 a pale brown band crosses the cells of the apical portion of the 

 wing ; several irregular pale brown clouds in the cells along 

 the posterior margin, leaving some pellucid spots alongside of 

 the margin. 



Hab. Missouri (Say) ; Washington, D. C, end of April ; 

 Illinois (Kennicott) ; Massachusetts (Scudder). 



In general appearance this species is very like the European 

 L. annulus Lin. ; but there are unmistakable differences in the 

 details. My female specimen shows no brown bands on the ab- 

 dominal segments ; this is undoubtedly accidental, as Wiedemann, 

 in describing a female, mentions them. 



2. L.9 immatura 0. S. % and J . — Thoracis vittis quatuor, femora 

 annulis tribus fuscis ; halterum capitulo apice pallido ; alae fusco- 

 maculatse et nebulosre, venula transversalis niarginalis juxta apicem 

 vense longitudinalis primse sita, macula fusca integra inclusa. 



Thorax with four brown stripes, femora with three brown bands ; the knob 

 of the halteres is pale at the tip ; wings spotted and clouded with brown ; 

 the marginal cross- vein is at the tip of the first longitudinal vein and is 

 included in a brown, entire (not ring-like) spot. Long. corp. 0.4 — 0.5. 



Syn. Limnobia immatura 0. Sacken, Proc. Ac. Nat. Sc. Phil. 1859, p. 214. 



Very like the preceding species, but showing the following 

 differences : it is smaller in size ; the femora, besides the two 

 brown bands beyond the middle, have a third one in the middle ; 

 it is pale, although distinct, especially on the anterior pair ; the 

 lateral edges of the abdomen are black, but there are no black 

 stripes on the posterior portion of the segments ; the spot at the 

 tip of the first longitudinal vein is entire, not ring-like ; the 

 gray band at the tip of the wing and the diluted clouds along 

 the posterior margin are much darker ; on the humeri there is a 

 large subtriangular brown spot, almost occupying the whole space 

 which is yellow in L. cinctipes ; the pleurae are darker; the basis 

 and the tip of the halteres are pale, the whole intermediate space 

 being dusky. 



Bab. Washington, D. C, in May; Upper Wisconsin River 

 (Kennicott) ; Maine (Packard). 



In this species, the fork formed by the subcostal cross-vein with 



