366 MOSQUITOES OF XORTH AMERICA 



Larva, Stage IV (plate 99, fig. 328). Head large, subquadrate, broader 

 than long, sides bulging, a notch at insertion of antennae, front margin arcu- 

 ate. Antennge rather large, basal two-thirds thickened, spinose, apical third 

 slender, a large tuft at set-off; two long seta? before tip, a long terminal seta, 

 a short one and a small digit on a pedestal. Both pairs of dorsal tufts and ante- 

 antennal tufts multiple. Mental plate with straight sides and triangular apex, 

 a large central tooth and eleven on each side, first three small and densely- 

 crowded, last one also small. Mandible quadrangular, two filaments before tip 

 with four short hairs arising from their base ; an outer row of cilia from a collar ; 

 a row of transverse prominences on outer margin bearing hair-tufts; dentition 

 of three rather widely separated teeth on a process, first longest; a long tooth 

 before, three at base, a filament within; process below undivided, with a few 

 hairs ; angle below sharp ; a group of hairs within and a row at base. Maxilla 

 conical, divided by a suture; inner half hairy on margin and in a band near 

 suture ; a tuft of long hairs at tip running along the suture ; outer half ^vith two 

 filaments about middle preceded by a few hairs, a spine on other side. Palpus 

 moderate, terminal digits rather long. Thorax rounded, wider than long; hairs 

 abundant, moderate, anterior thoracic hairs about as long as head. Anterior 

 abdominal segments short, posterior ones elongated; lateral tufts of first two 

 segments multiple, two hairs on third to sixth ; subdorsal hairs double on third 

 to sixth segments. Tracheal tubes narrow, irregularly flexuous posteriorly. 

 Air-tube elongate, slightly fusiform, five times as long as wide; pecten teeth 

 on basal third ; single tooth short, with four long basal branches ; several hair- 

 tufts beyond pecten the subapical one out of line. Lateral comb of eighth seg- 

 ment of numerous scales in a triangular patch, single scale with feathered tip. 

 Anal segment longer than broad, ringed by the plate ; dorsal hairs unequal, three 

 on a side; a single lateral hair; ventral brush well developed, confined to the 

 barred area. Anal gills longer than the segment, rather broad, tips bluntly 

 pointed. 



Pupa (plate 148, fig. 701). Thoracic mass subpyriform, stout; small hair- 

 tufts on thorax anteriorly; air-tubes moderate, slightly expanded, notched at 

 tip. Abdomen stout, with numerous hair-tufts, eighth segment with small 

 multiple hair-tufts on apical angles. Anal paddles elongate-ovate, with simple, 

 minute terminal seta. 



The eggs (plate 147, fig. 686) are laid arranged upright in boat-shaped 

 masses. They are subcylindrical and taper slightly to the upper end; micro- 

 pylar end broadly rounded. The number of eggs in a mass, according to counts 

 of ten masses by Davis, ranges from 120 to 309. 



The species occurs associated with man and is abundant in our northern 

 cities, breeding in various receptacles containing water. In America it is usually 

 rare or absent in the rural districts, being largely replaced by Culex restuans. 

 The females bite at night, but with the approach of cold weather cease to bite 

 and seek places for hibernation. The species appears to be less troublesome to 

 man than Culex quinquefasciatus. The males have been found feeding on the 

 honey of fiowers and do not hibernate. Schmitz reports that in Holland the 

 adults occur in caves throughout the year, Mr, Knab has observed the mating 

 habits of this species, and we have quoted his account in the first volume of this 

 work, page 121. 



Professor Smith has recorded numerous observations under the specific name 

 Culex pipiens, but without seeing his specimens we are unable to tell to what 

 species they actually refer ; probably to a mixture of Culex pipiens, Culex sal- 

 inarms, and Culex restuans. These three species breed indiscriminately in rain- 

 barrels, and are collectively known as " the house mosquito." 



