814 MOSQUITOES OF NOKTH AMERICA 



hind ones broadly silver tipped; fore tarsi with minute white spots at bases of 

 first and second joints and apex of first ; mid tarsi with first joint white, broadly 

 ringed with black before middle, second joint white on basal half; hind tarsi 

 with apical third of first joint and basal two-fifths of second joint white. Claw 

 formula, 1.1-1.1-0.0. 



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



Male. — Proboscis moderately long and slender, straight, violet-black scaled. 

 Palpi as long as the proboscis ; end of long joint somewhat thickened, the last 

 two joints rather short, slender, but slightly thickened ; terminal hairs moderate, 

 rather sparse, black ; vestiture blackish throughout. Antennae plumose, the last 

 two joints long and slender, rugose, pilose, black, the others short, sordid- 

 luteous, ringed with black at insertions of hair-whorls; hairs of whorls long, 

 dense, brownish-black. Coloration similar to the female ; antero-lateral silvery- 

 white patches of mesonotum larger and fused with ante-alar ones. Abdomen 

 elongate, subcylindrical, ventrally produced into a keel, the sixth and seventh 

 segments apically expanded beneath; lateral ciliation short, rather sparse and 

 irregular, dull luteous; eighth segment with silvery-white basal band above. 

 Wings narrower than in the female, the stems of the fork-cells longer, the 

 vestiture less abundant. Claw formula, 3.1-2.1-0.0. 



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



Genitalia (plate 32, fig. 216) : Side-pieces over twice as long as wide, 

 rounded at tips, apical and basal lobes absent. Clasp-filament small, slender, 

 with an articulated terminal spine half as long as filament. Harpes elliptical, 

 concave, inner margin revolute, tip pointed and recurved. Harpagones with 

 a columnar base bearing a terminal, articulated, long, narrowly ligulate fila- 

 ment. Unci approximate, revolute, forming a large basal cylinder. Basal 

 appendages very short, bearing five spines. 



Larva, Stage IV (plate 121, fig. 420). — Head rounded, slightly narrowed be- 

 fore eyes, a slight notch at insertion of antennse, front margin broadly arcuate. 

 Antennae moderate, slender, cylindrical, slightly curved, very slightly spined, 

 almost smooth; a single hair near middle; two long spines, two short ones, and 

 an apical digit. Eyes large, pointed. Both pairs of dorsal head-hairs single, 

 ante-antennal tuft multiple. Mental plate triangular, with a central tooth and 

 eleven on each side, basal ones slightly more remote. Mandible quadrangular, 

 elongate, with short basal spines ; two filaments before tip; an outer row of ciUa 

 from a collar; outer margin very oblique, with a row of filaments near the collar ; 

 dentition of four teeth on a process, the first longest ; two spines before, three 

 teeth at base, a broad filament and six slender ones vnthin; process below 

 slender, furcate, upper limb thick and rounded with a long hair-tuft at tip, 

 lower limb slender ; a row of hairs from base of incision to below the dentition ; 

 basal angle sharp; a row of hairs within; a row of hairs at base. Maxilla 

 rounded quadrate, elongate, divided by a suture ; inner half with a row of sharp 

 spines on the edge and a median oblique row of cilia, a hair-tuft at tip ; outer 

 half with a pair of filaments about the middle, arising from a process which 

 overlaps the suture ; palpus small, with the terminal digits irregular. Thorax 

 rounded, wider than long; subdorsal prothoracic hairs multiple. Abdomen 

 moderate, anterior segments shorter; lateral hairs of first segment multiple, 

 double on second to sixth. Air-tube stout, tapering outwardly, about two and a 

 half times as long as wide; pecten evenly spaced, running beyond middle of 

 tube, followed by a single tuft of three hairs ; single pecten-tooth a long spine 

 with a short basal branch. Lateral comb of eighth segment of many scales in a 

 triangular patch; single scale elongate, conical, smooth. Anal segment about 

 as long as wide, with a dorsal plate reaching well down the sides, narrowly in- 



