NOTES ON CULICIDAE. 203 



Owing to the larval and male genital stnictuie this is perhaps the most distinct of 

 the subgenera of the Aedes group, and were it not for the fact that I can find no definite 

 character to separate the females from Aedes I should prefer to retain it as a distinct 

 genus. 



(2) Subgenus Stegomijia, Theo. — Larva : antennae short, cylindrical, without 

 microscopic spines, the tuft minute and never more than two-haired ; frontal hairs 

 always single ; comb-scales in a single row. Male genitalia : claspers with a single 

 terminal or subterminal articulated spine ; side-pieces without apical lobes ; unci 

 usually more or less brush-like or pectinate. Male palpi usually long, thin, and Anthout 

 hair-tufts ; quite short in two species [amiidirostris and thomsoni). Female claws 

 toothed or not. Female abdomen without distinct cerci, the eighth tergite prominent, 

 but not the eighth sternite. Usually ornate species, frequently black and white, with 

 conspicuous white rings on the legs ; flat scales on head and scutellum, 



(3) Subgenus Ochlerotatus (Arr.) Edw. — Larva : antennae longer than in Stegomyia, 

 usually more or less curved and tapering, and covered with microscopic spines ; tuft 

 well-developed and nearly always many-haired ; frontal hairs usually multiple ; 

 comb-scales nearly always in a triangular patch. Male genitalia very diverse, but the 

 claspers M-ith a single articulated spine, which may or not be terminal. Male antennae 

 with the verticillate hairs more numerous dorsally and ventrally. Male palpi usually 

 long, with the last two joints somewhat swollen, hairy and bent downwards ; in a 

 few species {eatoni, etc.) only about half as long as the proboscis. Female claws 

 almost always toothed. Female abdomen with distinct projecting cerci, except in 

 one group. Ornamentation very diverse. 



The fui-ther classification of this subgenus is dealt with below. 



(4) Subgenus Aedes, Mg. — Larva, so far as known, like that of Ochlerotatus. Male 

 genitalia extremely diverse, even in closely allied species ; claspers without articulated 

 spine, sometimes much reduced. Male palpi very short. Male antermae with the 

 verticillate hairs less numerous and more evenly distributed than in Ochlerotatus. 

 Female claws toothed. Female abdomen with distinct cerci. Dark species, not 

 strikingly ornamental ; head mainly covered with flat scales. 



(5) Subgenus SJcfisea, Theo. — ^Larva not yet described. Male genitalia with five or 

 six long processes which have apparently been derived from the basal lobes of the side- 

 pieces, but in some cases have become nearly apical, resembling the somewhat similar 

 structures oiCulex. Male palpi long, hairy towards tip {pemhaensis), long, thin and 

 bare {amesii) or quite short {simplex). Female claws simple. Female abdomen 

 pointed, as usual, and with distinct cerci. 



Subgenus Armigeres, Theo. 

 The Oriental species of this subgenus are numerous and difficult to separate ; the 

 following is an attempt at a table of those in which the female palpi are short. A 

 table of those {Leicesteria group) which have the female palpi more than half as long 

 as the proboscis has been given previously. 



1. Hind femora on the outer side dark apicallv . . . . . . . . 2 



Hind femora on the outer side white to the tip . . . . . . . . 3 



2. All tibiae about equal in length . . . . . . . . nioidtoni, Edw. 



Hind tibiae distinctly the shortest . . . . . . . . brevitihia, Edw. 



(C325) ^ A 2 



