MOSQUITO BIOLOGY 163 



species occurs in favorable localities throughout at least the northern 

 half of the state. The period of flight is long, and as we have no indica- 

 tion that there is more than one brood, the period of flight indicates an 

 individual life of about three months. 



DESCRIPTION OF THE LARVA 



Full grown wriggler measures 12-14 mm. (.4!8-.56 inch) long, ex- 

 cluding anal siphon, dirty gray, excepting head and siphon, in general 

 build, resembles Aedes canadensis. Head almost as broad as long, widest 

 just below eyes, tapering without curve to beyond base of antenna, flat- 

 tened in front, light brown in color, with four small black spots near 

 base of vertex. On anterior part of vertex four single hairs, each arising 

 from separate pits ; pits so placed as to form square, slightly narrower 

 in front ; directly opposite posterior hair, at base of each antenna, 

 small tuft of four or five hairs. Antenna rather short, curved, uniformly 

 brown, surface sparsely set with short, stout spines and numerous small 

 ones scattered on basal half. Tuft of four or five hairs situated at mid- 

 dle, does not reach tip of antenna, which has apex terminated with one 

 long and one short spine, two short bristles and small articulated peg. 

 Eyes moderate size, semicircular, with small detached portion at pos- 

 terior edge. Rotary mouth brushes thick, composed of hairs pectinated 

 in the more central portion. Mentum triangular about as long as broad, 

 with slightly curved series of from twelve to fourteen small teeth on each 

 side of apex. Mandible normal, set with small spines at base. Maxillary 

 palpus short, very broad, hairs and spines arranged in patches on sur- 

 face, with a comparatively small apical tuft; basal joint rather large 

 with small, stout spines at apex. Thorax rounded, with rather short 

 hair tufts issuing from slight angles at sides. Anterior margin also, 

 with two short hair tufts. Abdomen long, anterior two segments trans- 

 versely oblong with lateral tufts of four or five hairs ; central and pos- 

 terior ones lengthened and narrower, with only two hairs to lateral tuft 

 up to segment seven. Eighth segment has lateral patches of from 

 twenty-eight to thirty-four scales, without any regular arrangement ; 

 single scale has spines at apex and along sides, apical one largest and 

 longest, other diminishing in size toward base. Anal siphon about four 

 times as long as wide at base and has two series of toothed spines, each 

 ranging from seventeen to twenty-two. Spines black, white-tipped, with 

 teeth not quite reaching middle ; common arrangement four teeth to 

 form two pairs. Ninth segment longer than wide, with the two dorsal 

 tufts and ventral row of tufts present, as usual. Tracheal gills only 

 slightly longer than ninth segment. 



