AEDES TRIVITTATUS 775 



Wings moderate, hyaline ; petiole of second marginal cell about half as long 

 as its cell, that of second posterior cell somewhat shorter than its cell ; basal 

 cross-vein distant about its own length from anterior cross- vein ; scales brown, 

 the outstanding ones narrowly ligulate. Halteres whitish, with pale brown 

 knobs. 



Legs moderately long, slender ; vestiture dark bronzy-brown ; under sides of 

 femora yellowish nearly to tip; knees narrowly white scaled. Claw formula, 

 1.1-1.1-1.1. 



Length : Body about 4.5 mm. ; wing 4 mm. 



Male. Proboscis moderate, straight, blackish brown scaled. Palpi exceeding 

 the proboscis by the length of the last joint ; end of long joint and last two joints 

 slightly swollen, with abundant long brown hairs ; vestiture dark brown without 

 rings, end of long joint black. Antennae plumose; last two joints long and 

 slender, rugose, pilose, black, the others short, brownish luteous, with narrow 

 black rings on the inerassated origins of the hair- whorls; hairs long, dense, 

 pale brown with yellowish reflection. Coloration similar to the female. Abdo- 

 men elongate, depressed, dorsally with narrow pale basal segmental bands, the 

 last segment entirely dark scaled ; lateral ciliation long, fine, abundant, pale 

 yellow. Wings narrower than in the female, the stems of the fork-cells longer, 

 the vestiture sparse. Claw formula, 2.1-2.1-1.1. 



Length : Body about 4.5 mm. ; wing 3.5 mm. 



Genitalia (plate 30, fig. 201) : Side-pieces about three times as long as wide, 

 apical lobe undeveloped, represented by a narrow expansion of the whole margin, 

 basal lobe rounded, hemispherical, small, setose and bearing a long, stout, hooked 

 spine. Clasp-filament slender, uniform with a long articulated terminal spine. 

 Harpes narrow, elliptical, inner margin revolute and thickened, tips sharply 

 pointed and recurved. Harpagones with slender columnar base bearing a ligu- 

 late filament which is expanded at the middle and bears a sharp retrose spine. 

 Unci approximate, revolute, forming a slender cone, cleft at tip. Basal append- 

 ages small, approximate, bearing four long spines. 



Larva, Stage IV (see figure of the entire larva, plate 68). Head rounded, 

 narrowed before eyes, a notch at insertion of antennae, the front margin arcuate. 

 Antennae slender with a small tuft at middle. Mental plate triangular, thick, 

 with a small central tooth and fourteen on each side, the basal ones somewhat 

 more remotely spaced, the last one small. Mandible quadrangular; two fila- 

 ments before tip ; an outer row of cilia from a collar ; a row of filaments along 

 outer margin; dentition of four teeth on a process, the first longest; a spine 

 before, a broad filament and six long feathered hairs within; process below 

 elongate, square, obscurely furcate, fringed with hair along outer margin and 

 with a tuft at apex ; basal angle moderate ; four hairs within ; a row of long ones 

 at base. Maxilla elongate hemispherical, divided by a suture ; inner half hairy, 

 a tuft of long hairs at tip; outer half with two long filaments very near the 

 apex and a spine on the other side ; palpus rather long, stout, with five irregular 

 digits at tip. Thorax moderate, the tufts of lateral hairs rather short. Abdo- 

 men elongate ; lateral hairs on segments 3 to 6 single. Air-tube over twice as 

 long as wide, conically tapered ; pecten reaching to beyond middle, evenly spaced, 

 teeth longer outwardly, about twenty in number ; a single tuft of about six hairs 

 beyond pecten ; single pecten-tooth a long spine with five short basal branches. 

 Lateral comb of eighth segment of about twenty scales in a patch nearly three 

 rows deep; single scale elongate, thorn-shaped, fringed with spinules at base. 

 Anal segment about as long as wide, ringed by the plate ; dorsal tuft a hair and 

 brush on each side ; ventral brush well developed, confined to barred area ; anal 

 gills moderate, ensiform. 



