AEDES BIMACULATUS 623 



bristles. Postuotum convex promineut, yellow-brown, nude. Pleurae brownish- 

 yellow, sometimes with a round black spot centrally toward the upper margin, 

 with several patches of broad silvery-white scales and rows of yellow bristles; 

 coxae with patches of golden scales. 



Abdomen subcylindrical, flattened, posterior segments tapered, the cerci 

 exserted; yellowish-brown, dorsally clothed with flat, dull orange-yellow scales 

 and very broad, subtriangular apical bands of dull black scales; venter with 

 the membrane dull luteous, the scales wholly orange-ochraceous ; setae fine, 

 golden, rather numerous ventrally; cerci with black tips. 



Wings large but rather narrow, hyaline ; petiole of second marginal cell much 

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

 cross- vein rather less than its own length distant from anterior cross-vein; 

 costal, subcostal and first veins yellow to apical fourth and with deep golden- 

 yellow scales, beyond the scales merging into dull brown; the other veins 

 wholly brownish and with dull brown scales; proximal portion of second vein 

 yellowish and with yellowish scales; outstanding scales on outer half of wing 

 lanceolate, broader and denser toward apex of wing; fringe dull brown. 

 Halteres yellow, with white tips. 



Legs long and rather slender ; femora yellow, with small golden -yellow scales, 

 extreme tips black scaled ; tibiae golden scaled, extreme bases and tips black, the 

 coarse setae black, on the hind tibiae some of the scales, especially apically, are 

 slightly erected; tarsi deep golden-yellow scaled, tips of joints bronzy -brown 

 scaled ; last three hind tarsal joints diffusedly bronzy-brown scaled. Claw for- 

 mula, 1.1-1.1-0.0. 



Length : Body about 5 mm. ; wing 4.5 mm. 



Male. Palpi long, exceeding the proboscis by nearly the length of the last two 

 joints, which are slender and very slightly enlarged; vestiture dark golden- 

 yellow, long joint with narrow black rings at the median false articulation and 

 apex ; penultimate joint basally black and with a black tip ; last joint almost 

 wholly black; end of long joint and last two joints with many long golden and 

 black hairs. Antennae plumose ; last two joints long and pilose, the others short, 

 yellowish, narrowly ringed with brown at the insertions of the hair- whorls ; hairs 

 long, blackish with brown luster. Coloration similar to the female. Wings 

 hardly narrower than in the female, the stems of the fork-cells longer and the 

 vestiture less abundant. Abdomen elongate, depressed, dorsally with very 

 narrow, black apical bands ; lateral ciliation coarse, pale brown. Claw formula, 

 2.1-2.1-0.0. 



Length : Body broken ; wing 4 mm. 



Genitalia (plate 24, fig. 170) : Side-pieces about three times as long as wide, 

 uniform, tips rounded ; a small narrow, lappet-shaped subapical lobe ; a similar 

 but larger basal lobe with a large spine at its base ; clasp filament long, slightly 

 swollen mesially, with a long terminally inserted spine. Harpes elliptical with 

 revolute margins, tips thickened and hooked. Harpagones with a slender col- 

 umnar stem slightly curved, terminal filament large, triangular, a basal angle 

 at one side, tip pointed. Unci forming a small basal cone. Basal appendages 

 narrow, with five setae, arising from a lobe of the penultimate segment. 



Larva, Stage IV (plate 118, fig. 406). Head rounded, narrowed before eyes, 

 a notch at insertion of antennae, front margin arcuate. Antennae cylindrical, 

 slender, slightly swollen towards base, smooth ; tuft small, situated before mid- 

 dle ; four irregular, short terminal spines and a digit on a long pedestal. Eyes 

 large, transverse, pointed. Upper pair of dorsal head-hairs single, lower double, 

 anteantennal tufts multiple. Mental plate triangular outwardly, teeth very long, 

 a central one and fifteen on each side, basal ones a little larger, suddenly ending, 

 followed by a small short tooth near base. Mandible quadrangular, broad, with 



