34 MOSQUITOES or NORTH AMERICA 



Wings narrow, hyaline, iridescent ; petiole of second marginal cell one-third 

 as long as the cell, that of second posterior cell shorter than its cell ; cross-veins 

 nearly incident ; scales of veins black, with a bronzy and blue reflection, elliptical, 

 mostly obliquely subtruncate; those on forks of second vein denser. Halteres 

 blackish, except at base. 



Legs moderate, the vestiture black, with a blue and violaceous reflection, 

 slightly roughened beneath at tips of hind tibise and base of first tarsal joint ; 

 last joint of hind tarsi white on inner side. Claw formula, 0.0-0.0-0.0. 



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



Male. — Entirely similar to the female, claws of fore feet slightly unequal, tip 

 of abdomen expanded and truncate, scales at tip brilliantly iridescent; legs with 

 a coppery luster beneath. 



Genitalia (plate 2, fig. 4) : Side-pieces over twice as long as wide, the tips 

 conically tapered, a small, scarcely separated lobe at the base bearing two stout 

 setae and a number of fine hairs. Clasp-filament with a large, inflated, dis- 

 torted branch, a slender inward branch at basal third long and recurved, a small 

 branch at outer third curved, with a bent, divided tip, apex slightly inflated, 

 bearing a series of spines at the tip, outer aspect pilose, a large inward inflated 

 projection at outer third bearing a long marginal row of coarse teeth and a 

 shorter finer submarginal row. Harpes flat, tapering outwardly, inner margin 

 revolute, tip dentate. Harpagones and unci forming basal cones. Basal append- 

 ages represented by two groups of four spines each, remote from one another. 



Larva, Stage IV (see figure of the entire larva, plate 42). — ^Head rounded 

 (plate 131, fig. 463), side-angles obtusely rounded, a slight notch at insertion of 

 antennae, front margin broadly arcuate. Antennae cylindrical, smooth, uniform, 

 without hair; a long spine, two short ones and a long digit at tip. Eyes small, 

 round. MenM plate square, nearly straight on front edge, a prominent central 

 tooth and eight on each side, the last one largest; base wavily incised. Mandible 

 quadrangular; an appendage before tip; an outer row of cilia from a coUar; ten 

 filaments on outer margin ; dentition of four teeth on a process, the first much the 

 largest; a spine before, a low double irregularity at base, a serrate filament and 

 three feathered ones within ; process below remote, taking the place of the basal 

 angle, short, furcate, with long hairs at tip and a row of &ie hairs between it and 

 the dentition; a row of long hairs within; a basal row. Maxilla conical, the tip 

 produced into a long, stout horn; divided by a suture; inner half with four large 

 teeth and a small one on margin and two rows of cilia ; a tuft of hairs at tip, 

 arising from base of horn; two rudimentary filaments next the suture; a long 

 spine from middle of outer half, its tip cleft. Palpi small, obliquely attached, 

 with four minute digits. Thorax quadrangular, slightly rounded at the comers, 

 wider than long, the mesothorax indicated; hairs long, the metathoracic ones 

 with a posterior curved spine. Abdomen slender; hairs abundant, lateral tufts 

 of first two segments multiple, single on third to sixth segments; short hairs in 

 coarse, stellate bunches. Trached tubes moderate. A pair of simple dorsal 

 hooks on seventh segment. Air-tube long, ten times as long as wide, strongly 

 flared at base ; surface densely spicular, with some hairs ; no pecten.' Lateral 

 comb of eighth segment of eight simple spines; single spine thorn-shaped, the 

 shaft smooth, the base fringed with short spinules. Anal segment as wide as 

 long, dorsal plate reaching to middle of side; dorsal tuft of long hairs; a tuft of 

 two long hairs at lateral angle of the plate ; a subventral tuft of three long hairs ; 

 no ventral brush. Anal gills long, all four present three times as long as the 

 segment, basal portion swollen, outer slender. 



The larvae occur in the water in bamboo-joints, often in considerable numbers. 

 Mr. Busck states that they hang perpendicularly by the air-tube from the surface 



