568 MOSQUITOES OF NORTH AMERICA 



dark brown; scales black, the outstanding ones broadly linear and ligulate. 

 Halteres pale, with blackish knobs, a patch of white scales at tips. 



Legs moderately long, a few scales at apices of posterior tibiae obliquely out- 

 standing; femora yellow, with small golden scales, a line on upper side and 

 an apical ring of blue-black scales; knees very narrowly silvery- white scaled; 

 tibiae and tarsi entirely clothed with appressed blue-black scales and short, stiff 

 black bristles. Claw formula, 1.1-1.1-1.1. 



Length : Body about 5 mm. ; wing, 4 mm. 



Male. Proboscis straight, slender. Palpi long, exceeding the proboscis by 

 nearly the length of the last two joints, which are both stout and swollen; 

 membrane blackish, vestiture entirely of metallic violaceous scales, apex of 

 long joint and last two joints with many long black hairs. Antennas plumose ; 

 last two joints long and pilose, the others short, pale, with broad dark rings at 

 insertions of the hair-whorls ; hairs of whorls long, dense, brown. Coloration 

 similar to the female. Abdomen elongate, depressed, with long and abundant 

 black lateral ciliation. Hind tibiae with rather sparse long and prominently 

 outstanding scales; many long hairs on femora, tibias, and tarsi. Wings nar- 

 rower than in the female, without brownish costal tinge, the veins paler brown. 

 the stems of the fork-cells longer. Claw formula, 2.1-3.1-1.1. 



Length : Body 6 mm. ; wing 5 mm. 



Genitalia (plate 22, fig. 158) : Side-pieces with conical tips, rather more than 

 twice as long as broad, without apical or basal lobes. Clasp-filament swollen 

 beyond middle, the enlargement on the inner side, marked in a reticulate pattern 

 and fringed on inner aspect with minute setse and short denticles ; a rather long 

 terminal articulated spine. Harpes laminate, elliptical, outer margins thick- 

 ened and revolute with several small apical dentations. Harpagones long, with 

 a slender ligulate base and expanded fan-shaped tip bearing a row of eight stout 

 setae from produced bases. Unci approximate at tips, elliptical, flat, both mar- 

 gins revolute, a group of small spines below base of side-pieces on either side. 



Larva, Stage IV (plate 116, fig. 400). Head rounded, transverse, somewhat 

 elliptical, not widened through eyes; antennae large, stout, minutely densely 

 spined, a two-haired tuft near middle, terminal setae short; dorsal head-hairs 

 single, ante-antennal tufts in threes. Lateral comb of eighth segment of four 

 large scales on a weak chitinous plate, each scale broad, with spines at corners 

 and a long central spine. Air-tube inflated, fusiform, with three separated pecten 

 teeth near base ; a long hair on each side at tip arising from lateral respiratory 

 flap. Anal segment a little longer than wide, ringed by a chitinous band ; dorsal 

 tufts of a long hair and tuft on each side ; ventral brush continued along ventral 

 line nearly to base. Anal gills long, equal, pointed. 



The eggs are black and laid singly, according to the observations of Mr. W. 

 E. Hinds. The larvas develop in temporary puddles immediately after rains. 

 Mr. Thibault gives the following account of the adults : 



" Very abundant in suitable localities after rains, in fields, thickets, and about 

 dwellings. Does not enter dwellings. The appearance of this mosquito im- 

 mediately after rains is so strikingly characteristic that even people who never 

 pay much attention to such things notice it. They are out in force for several 

 days after a rain and then only a few will be found until the next rain. 



" The most annoying of all mosquitoes when occurring abundantly, not only 

 to human beings, but to all kinds of stock. They are very persistent and hard 

 to kill unless you hit them a real hard blow. The only mosquito, so far as I 

 know, that will at all times come out into the sunshine on the very hottest days 

 and bite. They gorge themselves until they literally fall to the ground, almost 

 unable to fly at all. They never voluntarily quit biting, but stay in the same 

 place for hours (on horses especially) until literally pulled off. In this way 



