598 MOSQUITOES OF NORTH AMERICA 



at the sides a patch of broad, flat black scales, the cheeks covered with broad, flat, 

 silvery white scales ; eyes bordered by a row of curved black bristles. 



Prothoracic lobes moderate, elliptical, remote dorsally, clothed with narrow, 

 curved white scales and with black bristles. Mesonotum uniformly rich dark 

 brown, a median and sublateral rows of black bristles; vestiture of sparse, 

 minute, curved golden-brown scales, a diffused patch of larger silvery-white 

 ones at anterior angles, medianly a pair of large, diffused, transverse patches 

 behind and above the lateral depressions, some of these silvery scales scattered 

 over the disk, a large patch in front of the ante-scutellar bare space, and one on 

 each side of this next the scutellum, another over the roots of the wings ; bristles 

 black, numerous at roots of wings. Scutellum trilobate, dull luteous, each lobe 

 with a large patch of narrow, curved silvery-white scales and about eight black 

 bristles. Postnotum elliptical, prominent, dark brown with a slight whitish 

 pruinosity, nude. Pleurae and coxas brown, clothed with narrow, elliptical, flat 

 white scales and brownish bristles. 



Abdomen subcylindrical, flattened, tapering posteriorly, the cerci prominently 

 exserted ; dorsal vestiture of black scales with a brown luster, the apices of the 

 segments with narrow silvery-white bands interrupted in the middle, each 

 succeeding one more broadly so, last segment wholly black ; first segment with a 

 median patch of black scales and with many pale hairs ; sides with an irregular 

 row of white scales forming an ill-defined line; venter clothed with whitish- 

 golden scales, except sides at last segment, which are dark brown; setae short, 

 black dorsally, golden ventrally. 



Wings rather broad, hyaline, iridescent; petiole of second marginal cell 

 shorter than its cell, that of second posterior cell also shorter than its cell ; basal 

 cross- vein rather less than its own length distant from anterior cross-vein; 

 veins brown; scales brownish black throughout, outstanding ones narrowly 

 ligulate, those on fork of second vein denser and narrowly lanceolate. Halteres 

 entirely pale. 



Legs moderately long and slender; femora clothed with pale-yellow scales 

 below towards base, upper side and tips black, extreme base and apex white, a 

 narrow white ring before apical fourth ; tibiae black, with about nine little white 

 spots along sides, the anterior pair with only a few white spots ; tarsi black, each 

 joint with a narrow white basal ring which is almost obsolete on fore and 

 middle tarsi, the last two joints being entirely black, last joint of hind pair 

 with the basal third white. Claw formula, 0.0-0.0-0.0. 



Length : Body about 4.5 mm. ; wing 3.5 mm. 



Male. — Proboscis straight, black scaled, with a narrow white ring beyond 

 middle. Palpi exceeding the proboscis by nearly the length of the last two joints, 

 which are long, subcylindrical, hardly enlarged ; vestiture black, with a narrow 

 white ring at base of last two joints and near middle of long joint ; end of long 

 joint and last two joints with rather short black hairs. Antennae plumose, the 

 last two joints long and pilose, the others short, black at insertions of hair- 

 whorls and whitish beyond; hairs of whorls long, dense, brovm. Coloration 

 similar to the female. Abdomen long, depressed ; the silvery apical segmental 

 bands much broader than in the female and distinctly divided in the middle, 

 especially posteriorly, the last segment with a large silvery-white apical patch ; 

 lateral ciliation long and abundant, brown. Wings narrower than in the female, 

 the stems of the fork-cells longer, the vestiture less abundant. Claw formula, 

 1.0-1.0-0,0. 



Length : Body about 5 mm. ; wing 3 mm. 



Genitalia (plate 22, fig. 157) : Side-pieces more than twice as long as wide, 

 conically tapered, apical lobe prominent, triangular, basal lobe absent ; clasp- 

 filament stout, strongly swollen medially, reticulate, a moderate stout articulated 

 terminal spine. Harpes flat, concave, inner margin thickened and revolute, 



