764 MOSQUITOES OF NOKTH AMERICA 



Description oi- Femau:, Maij;, Laeva, Pupa, and Bfeo of Aedbs triseeiatus: 



Female. — Proboscis rather long and slender, subcylindrical ; labellae conically 

 tapered; vestiture black; setse minute, curved, black, those on labellse more 

 prominently outstanding. Palpi short, less than one-fourth the length of pro- 

 boscis, clothed with black scales ; bristles rather long, black. Antennae slender, 

 filiform, the joints subequal, rugose, pilose, black ; second joint a little swollen 

 towards base, pale at its basal insertion ; tori subspherical, with a cup-shaped 

 apical excavation, luteous, black on inner side with some minute black setse; 

 hairs of whorls moderate, sparse, black. Clypeus roundedly triangular, promi- 

 nent, black, nude. Byes black. Occiput black, clothed with narrow, curved, 

 yellowish silvery- white scales on vertex, flat silvery-white ones on the sides; 

 many erect, forked, pale-yellowish scales on the nape ; setse along margins of eyes 

 black, those projecting between the eyes pale yellow. 



Prothoracic lobes elliptical, remote dorsally, blackish, largely clothed with 

 flat silvery-white scales and pale bristles. Mesonotum black, clothed with nar- 

 row curved scales, deep brown on dorsum, silvery-white at anterior margin and 

 on the sides, the white forming a deep indentation at the middle of the sides, the 

 dorsal brown area widening behind the middle and divided behind by the ante- 

 scutellar space, which is edged with silvery-white scales. Scutellum trilobate, 

 clothed with whitish scales, each lobe with a group of brownish black bristles. 

 Postnotum elliptical, prominent, brownish, nude. Pleurse blackish, coxae 

 luteous, clothed with patches of flat triangular silvery-white scales and rows of 

 pale bristles. 



Abdomen subeylindrical, tapering posteriorly; dorsal vestiture blue-black, 

 with pale bristles at ends of segments, a series of large, triangular, silvery-white, 

 lateral basal segmental patches extending beneath nearly to apices of segments ; 

 venter silvery-white, apices of sixth and seventh segments blue-black. Cerci 

 black. 



Wings rather narrow, hyaline, slightly infuscated ; petiole of second marginal 

 cell shorter than its cell, that of second posterior cell also somewhat shorter than 

 its cell; basal cross- vein more than its own length distant from anterior cross- 

 vein ; scales on veins blue-black or brown, the outstanding ones narrowly ligu- 

 late. Halteres whitish. 



Legs rather long and slender; hind femora yellowish-white on basal third 

 above, on basal two-thirds below, the rest blue-black; knees white; fore and 

 mid femora black above to base ; tibiae blue-black, the tips of tibiae slightly yel- 

 lowish, fore and mid pair pale scaled beneath ; tarsi entirely blue-black scaled. 

 Claw formula, 1.1-1.1-0.0. 



Length : Body about 4.5 mm. ; wing 4 mm. 



Male. — Proboscis straight, moderately long, black scaled. Palpi slightly 

 longer than the proboscis, blunt at tip, black sealed, a minute white ring before 

 middle of long joint; last two joints and end of long joint slightly thickened 

 and with long black hairs. Antennae plumose, the last two joints long and 

 slender, rugose, pilose, black, the others whitish, black at insertions of hair- 

 whorls; hairs of whorls long, dense, black, with brownish luster. Coloration 

 similar to the female. Abdomen elongate, slender, depressed; lateral spots on 

 segments 5, 6 and 7 very large, eighth segment nearly entirely white scaled; 

 venter black scaled, with segmental basal silvery bands ; lateral ciliation moder- 

 ately abundant, irregular, of fine pale hairs. Wings narrower than in the female, 

 the stalks of the fork-cells longer, the vestiture hardly less abundant. Claw 

 formula, 1.1-1.1-0.0. 



Length : Body about 6 mm. ; wing 4.5 mm. 



Genitalia (plate 31, fig. 207) : Side-pieces about twice as long as wide, conical, 

 basal and apical lobes absent; a small area of dense setae representing the basal 



