292 



F. W. EDWARDS. 



4-6, in a posterior row overlapping the spiracle. Spiracular bristles absent. 

 Post-spiraciilar, pre-alar, stemopleural and upper mesepimeral bristles all present 

 and generally numerous. Postnotum without setae. Eighth segment of female 

 abdomen retractile, a wide membrane between it and the seventh. Side-pieces 

 of male hypopygium with a lacuna of chitinisation extending the whole length 

 of the inner side ; claspers articulating in an horizontal plane. Tenth segment 

 with tergites feebly developed ; stemites simple, without teeth or spines. Hind 

 tibiae with the usual row of fine microscopic hairs just before the tip on the 

 inner side, and also with a row of 7-10 longer hairs parallel with the first row 

 and slightly more distally placed. First hind tarsal joint shorter than the 

 tibia. Pulvilli absent. Front and middle claws of female nearly always 

 toothed. Cell R, (upper fork-cell) seldom much longer than its stem. Vein A„ 

 (sixth longitudinal) terminating distinctly beyond the level of the base of Rg (second 

 vein). Distinct microtrichia on wing-membrane. 



Fig. 5. Structural details of Culicidae : a, tip of hind tibia, seen from the inner side, of Culex 

 hortensis (scales omitted), x 65; b, the same structure in Aides lepidonotus ; c, the same in Thecbaldia 

 fumipennis ; d, tip of last tarsal joint of Lukia vorax, showing claws, empodium and pulvilli, 

 X 340 ; e, tip of last tarsal joint of Theobaldia annulata, showing claws, small empodium, and 

 absence of pulvilli, x 340 ; f, tip of abdomen of A'edes lepidonotus^, showing slender eighth 

 segment with narrow sternite, x40; g, the same, A'edes geniculatuso, showing stouter eighth 



segment with broader sternite. 



Larva. — Mouth-parts not specially modified for predaceous habits, but the inner 

 hairs of the mouth-brushes are generally more or less serrate. Antennal tuft generally 

 at or before the middle. Abdomen without chitinous plates except for the anal 

 saddle, and sometimes small plates at the bases of the thoracic hairs. Eighth segment 

 with a lateral comb or patch of scales. Siphon unmodified, short and stout, at most 

 four times as long as its breadth at the base, provided with a well-developed pecten 

 and a single pair of ventral hair-tufts, situated about or beyond the middle ; only 

 very exceptionally with accessory dorsal hairs or hair-tufts. 



As pointed out by Dyar (Insecutor Inscitiae, vi, p. 71, 1918) the genus can be 

 divided into two main groups, on the presence or absence of distinct claspettes in 

 the male hypopygium (the term claspette in this connection signifying a definite 

 structure separated from the base of the upper flap of the side-piece, and terminating 

 in a flattened appendage or a more or less modified bristle). Dyar's two groups may 



