500 MOSQUITOES OF XOETH AMEEICA 



outer side ; second marginal cell less than twice as long as stem ; second posterior 

 cell longer than its stem and farther from the base than the second marginal 

 cell. Halteres whitish, with black knobs. 



Legs black, mottled with dull white; front femora mottled black and white 

 beneath ; middle and hind femora whitish beneath, except at apex ; knees white ; 

 tibise tipped with white ; on front and mid legs the bases of second, third, and 

 fourth tarsal Joints rather narrowly white ringed; hind feet with second and 

 third joints broadly white ringed, the fourth narrowly so ; apices of first and 

 second tarsal joints on all the legs narrowly white scaled, the first joint with a 

 white mark at base above. Claw formula, 0.0-0.0-0.0. 



Length 6.5 mm. ; wing 7 mm. 



Male. Proboscis straight, long and slender, uniform; vestiture black, light- 

 gray scaled beneath, nearly to tip. Palpi slightly longer than the proboscis, the 

 outer part of long joint and the last two joints thickened and bearing long hairs, 

 the last joint only moderately thickened ; vestiture blackish, a very narrow pale 

 ring at middle of long joint and patches of white scales at bases of last two 

 joints. Antennae plumose; last two joints long and slender, black, the others 

 short, light colored, with thick black rings at the insertions of the hair- whorls ; 

 hairs very long, rather dense, brown. Abdomen with the pale basal bands 

 as in the female ; last segment entirely white scaled above ; elaspers dark scaled ; 

 venter entirely light scaled, two large dark patches at sides towards hind angles 

 of segments ; lateral ciliation long, abundant, luteous. Wings narrow, the stems 

 of the fork-cells longer than in the female, cross-veins nearly incident. Tarsal 

 claw formula, 3.1-2.1-0.0. 



Length: Body about 7 mm,; wing 6.5 mm. 



Genitalia (plate 35, fig. 233) : Side-piece stout, tapering gradually to a 

 broadly rounded af)ex; basal lobe wide, expanded, setose, two very stout long 

 setge contiguous at summit; outer lobe slight, represented by a small, densely 

 haired area which is slightly elevated. Clasp-filament slightly enlarged at base, 

 tapering outwardly, with a small terminal articulated spine. Harpe stout, with 

 broadly expanded base, apical portion curved, scarcely dilated, with a terminal 

 point and one or two small outer spines. Harpagones apparently wanting, per- 

 haps very membranous, invisible. Unci stout, rather slender, covolute, acute 

 apically with recurved points. Basal lobes rounded, bearing tufts of long, fine, 

 dense setse. The genitalia are extremely similar to those of the European 

 Culiseta annulatus Schrank, as figured by Dr. Felt (Bull. 97, N. Y. State 

 Museum, p. 480, pi. 12, fig. 2, 1905), 



No observations have been made upon the habits or early stages of this species. 



North America in the northwestern part of the continent, from the moun- 

 tains of western Canada northward. 



Fort Egbert, Eagle, Alaska, May 30, June 2, 1906 (Miss Ludlow's cotypes) ; 

 Koyukuk Eiver, Alaska, latitude 67 to 69, longitude 151, 1901 (W, J, Peters )j 

 Laggan, Alberta {3. Fletcher) ; Banfl", Alberta (N. B. Sanson) . 



Osten Sacken reports what is probably this species, under the name Ciilex 

 annulatus, from the Mackenzie Eiver. 



This species comes close to the European Culiseta annulatus, by the character 

 of the male genitalia, but the white markings are much less developed, the 

 Alaskan form lacking the white rings subapically on the femora and medianly 

 on the first tarsal joints. We therefore hold it as a separate species. 



