684 MOSQUITOES OP NORTH AMERICA 



medianly produced basal band of creamy or white scales and a narrow line of 

 pale ones at tip, on the sides the bands widen into wide triangular spots, espe- 

 cially on the sixth and seventh segments; first segment with a large patch of 

 white scales and many pale hairs ; venter clothed with pale ocherous scales with 

 some black ones intermixed, occasionally forming an imperfect median longi- 

 tudinal stripe. Cerci black. 



Wings moderate, hyaline ; petiole of second marginal cell somewhat shorter 

 than its cell, that of second posterior cell about as long as its cell; basal cross- 

 vein less than its own length distant from anterior cross-vein; scales of the 

 veins black with white ones intermixed, rather evenly distributed, the white 

 predominating on the subcostal vein, the black scales elsewhere; outstanding 

 scales long, broadly linear with blunt tips. Halteres entirely pale. 



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

 below, black and whitish ones about evenly intermixed above, the tips narrowly 

 pale ; tibiae with black and whitish scales intermixed, the black ones predominat- 

 ing at apices, the stiff outstanding setae mostly black; tarsi black, each joint 

 of hind ones with a broad basal ring of white scales, the first joint with some 

 white scales scattered over the surface ; on the front and middle tarsi the bands 

 are narrow, the last two joints of the front tarsi and the last joint of the mid 

 being wholly black. Claw formula, 1.1-1.1-1.1. 



Length : Body about 5 mm. ; wing 4.5 mm. 



Male. — Proboscis slender, straight. Palpi exceeding the proboscis by nearly 

 the length of the last joint; end of long joint and last two joints somewhat 

 thickened and bearing many long brown hairs with some yellow ones inter- 

 mixed ; long joint clothed with black and white scales, a band of whitish ones at 

 the middle, bases of last two joints with many white scales. Antennae plumose, 

 the last two joints long and slender, black, rugose, pilose, the others short, pale, 

 with thick black rings at insertions of hair-whorls ; hairs of whorls long, dense, 

 black and yellowish-brown. Coloration similar to the female. Wings narrower 

 than in the female, the stems of the fork-cells longer ; vestiture sparse. Abdo- 

 men elongate, depressed, the basal segmental bands broader; lateral ciliation 

 long, abundant, pale brown. Claw formula, 1.1-1.1-1.1. 



Length : Body about 5 mm. ; wing 4 mm. 



Genitalia (plate 25, fig. 173) : Side-pieces over twice as long as wide, slender, 

 distal lobe roundedly prominent, continued along inner margin narrowly to 

 basal lobe; basal lobe triangularly expanded, bearing many small setae with 

 tubercular bases and a single stout spine. Clasp-filament slender, bearing a few 

 small setae outwardly, at tip a long articulated terminal spine. Harpes slender, 

 concave, inner margins revolute, hooked at tip, point directed outward. Har- 

 pagones with a slender cylindrical base, slightly curved, minutely pilose, bearing 

 a short terminal filament which has a small point at base and curved pointed tip. 

 Unci approximate, revolute, forming an indistinct basal cylinder. Basal append- 

 ages stout and approximate, bearing a row of stout setae at tip. 



Larva, Stage IV (see figure of the entire larva, plate 64). — Head rounded, 

 wide behind, narrowed before eyes, slightly notched at insertion of antennas, 

 the front margin broadly arcuate. Antennae clindrical, slender, rather densely 

 spined throughout, the tuft moderately large, situated before middle; four 

 unequal terminal spines, the two larger shortly subapical, a small digit. Eyes 

 large, transverse, pointed. Both pairs of dorsal head-tufts and the ante-anten- 

 nal tuft multiple. Mental plate triangular, with central tooth and ten on each 

 side, becoming larger and more remote basally, the last two small and irregular. 

 Mandible quadrangular, a few short spines at base; two filaments near tip; an 

 outer row of cilia from a collar ; eight filaments on outer edge ; dentition of four 

 teeth on a process, the first longest, a curved spine and large double tooth at base, 



