304 MOSQUITOES OF NORTH AMERICA 



middle tarsal claws of male with one tooth under one of the claws, none under the 

 other, claws of the hind tarsi and all claws in the female simple. Length 3 mm. 



Port Limon, Costa Rica. Seven males and five females collected by Mr. F. Knab. 



Type. No. 8298, U. S. National Museum. 



Descbiption of Female, Male, and Laeva of Culex latisquama: 



Female. Proboscis rather long, subcylindrical, slightly expanded at tip, 

 lahellae conically tapered, pale; vestitnre of black scales, with a bluish reflection. 

 Palpi short, one-fifth as long as the proboscis, slender, black, with a few out- 

 standing setse. Antennae rather long, with the joints subequal, rugose, pilose, 

 black, second joint unusually long, cylindrical, half as long again as the suc- 

 ceeding one, pale at base ; tori subspherical, with a cup-shaped apical excavation, 

 luteous, black within ; hairs of whorls sparse, moderate, black. Clypeus rounded 

 triangular, doubly excavated at base, blackish brown, nude. Occiput blackish 

 brown, clothed with narrow, curved, dark lustrous-brown scales, many erect, 

 forked black scales with a coppery luster on the nape, cheeks dull whitish 

 scaled ; a row of bristles along ocular margins. 



Prothoracic lobes elliptical, remote dorsally, clothed with pale-brownish scales 

 and brown bristles. Mesonotum dark brown, with two narrow impressed lines ; 

 vestiture of narrow, curved, dark bronzy-brown scales and rows of long black 

 setae. Scutellum trilobate, testaceous, clothed with minute, curved dark-brown 

 scales, each lobe with a tuft of black bristles. Postnotum elliptical, prominent, 

 brown, nude. Pleurse and coxse brownish, with a large patch of elliptical flat 

 scales, bluish or yellowish white, according to the light. 



Wings ample, hyaline ; petiole of second marginal cell one-fourth as long as 

 its cell, that of second posterior cell much shorter than its cell ; basal cross-vein 

 more than its own length distant from anterior cross-vein ; scales dark brown, 

 black with a bluish luster on the costa, outstanding ones dense, ovate, densest 

 on forks of second vein. Halteres whitish with darker knobs. 



Abdomen subcylindrical, truncated at tip ; dorsal vestiture black with a slight 

 metallic reflection, a row of lateral, triangular, basal, segmental, yellowish-white 

 spots; venter yellowish-white scaled, with broad indistinct brown apical seg- 

 mental bands. 



Legs rather slender ; front and mid femora swollen and flattened, especially 

 the mid pair ; thickest at basal third ; femora white at base and beneath nearly 

 to tips ; vestiture otherwise black, with a blue reflection above and a bronzy one 

 beneath. Claw formula, 0.0-0.0-0.0. 



Length : Body about 4 mm. ; wing 3.5 mm. 



Male. Proboscis straight, hardly longer than in the female, but gradually 

 expanded towards apex. Palpi one-half as long as proboscis, very slender, uni- 

 form, with a few set* at tip ; long joint without median constriction, penulti- 

 mate about twice as long as thick, last joint minute ; vestiture of blackish scales, 

 without ciliation. Antenna longer than the proboscis, sparsely plumose; last 

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

 shorter, but four times as long as wide, fusiform, only slightly thickened at 

 insertions of hair-whorls, whitish on basal half, dark beyond the black rings at 

 insertions of hair-whorls ; hairs long, brown. Coloration similar to the female. 

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

 subcylindrical, hardly longer than in the female, somewhat thickened towards 

 apex, without distinct lateral spots, coarsely hairy apically, but without the 

 usual lateral ciliation. Claws of front and middle legs unequal, of hind ones 

 small and equal; formula, 1,0-0.0-0.0. 



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



Genitalia (plate 8, fig. 54) : Side-pieces more than twice as long as wide, with 

 a conically tapered tip ; marginal appendages on a slight subapical prominence 

 consisting of a smaller and a larger rod, with, cup-shaped expanded tips and 



