836 MOSQUITOES OF NORTH AMERICA 



Male. Proboscis straight, long and slender. Palpi as long as the proboscis, 

 slender, uniform; terminal joints with a few stiff setae; vestiture black, with 

 four wliite rings, situated at base and middle of long joint and at bases of last 

 two joints, the one at middle of long joint broad. Antennae plumose, the last 

 two joints long and slender, rugose, pilose, black, the others short, whitish, with 

 black rings at insertions of hair-whorls; hairs of whorls fine, rather dense, 

 brown. Coloration similar to the female. Abdomen elongate, strongly depressed, 

 the sixth and seventh segments broadened apically; dorsal vestiture black, the 

 second to sixth segments with laterally abbreviated basal white bands, absent on 

 seventh and eighth segments, the fifth to eighth segments with lateral or sub- 

 lateral silvery spots ; venter with first to sixth segments basally yellowish-silvery 

 scaled and apically black-scaled, the black becoming fused into a median line on 

 basal three segments, seventh and eighth segments black-scaled ; lateral ciliation 

 sparse, of rather coarse pale hairs. Wings narrower than in the female, the 

 stems of the fork-cells longer; vestiture less abundant. Claw formula, 1.0- 

 0.0-0.0. 



Length : Body about 4 mm. ; wing 3 mm. 



Genitalia (plate 33, fig. 224) : Side-pieces about one and one half times as 

 long as wide, tips conically tapered, without apical or basal lobes, but the inner 

 halves covered with fine hairs. Clasp-filament slightly enlarged in middle, 

 stout, with a short apical articulated spine. Harpes flat, plate-like, with a long 

 projection at base inward, tips rounded and excurved, a thin pilose membrane 

 between, squarely emarginate in middle. Harpagones wanting. Unci approxi- 

 mate, not confluent, with revolute margins and serrated tips. Basal appendages 

 wanting. 



Egg (plate 145, fig, 668, and plate 147, fig. 684). Fusiform, black, very 

 slightly flattened on one side, slightly more tapered toward the micropylar 

 end; sculpture of rough, somewhat irregular rhomboidal callosities forming 

 spiral rows. Length .53 mm., diameter .15 mm. 



Larva, Stage IV (see figure of the entire larva, plate 76). Head rounded, 

 wider than long, widest behind eyes, a slight notch at insertion of antennae, 

 front margin broadly arcuate. Antennae small, cylindrical, slightly curved, 

 smooth, a single hair at middle ; four terminal stout spines, two long, two short, 

 a small digit articulated on a pedestal. Eyes large, transverse, pointed. Both 

 pairs of dorsal head-hairs and ante-antennal hairs simple, all short. Men- 

 tal plate rounded triangular, central tooth large, with twelve on each side, sub- 

 equal, the median ones approximated, the outer ones more remote and slenderer. 

 Mandible subquadrate, nearly smooth without; two filaments before a notch 

 near tip ; an outer row of coarse cilia ; a row of small filaments beyond ; denti- 

 tion of four teeth, the first largest, a group of filamentous processes at base, 

 feathered setae within; a lobe below as long as the dentition, furcate at tip, 

 setose; five long hairs below; five still larger ones at base. Maxilla elongate 

 hemispherical, divided by a narrow suture ; inner half with a notch at the end 

 of a row of processes, hairy, a tuft of long hairs at tip ; outer haK with two 

 processes on one side and one on the other; palpus short, arising from outer side 

 of maxilla and appressed to it, less than twice as long as wide, with two very 

 small terminal digits. Thorax rounded, wider than long ; hairs moderate, rather 

 sparse. Abdomen rather long, sixth and seventh segments elongated; lateral 

 hairs of first segment quadruple, triple on second to fourth, double on fifth, 

 single on sixth; tracheal tubes broad, band-shaped. Air-tube stout, short, 

 strongly tapered on outer half, over twice as long as wide ; pecten running nearly 

 halfway, followed by a single tuft of few hairs ; single pecten-tooth a rather long 

 spine with two large and some small teeth within and small ones without. 



