Genus Culex. 
327 
them as of any further use otherwise than specifically. The 
male genitalia again vary so much in closely-related gnats that 
they I found useless, but in the scales 1 observed great variations 
and great uniformity in certain groups of mosquitoes, and thus 
I have adopted them for generic and sub-generic characters in 
breaking up this genus. The result is that it is reduced to some 
extent, but still retains a very large number of species, which 
will probably be still further isolated on more careful examination. 
-As Linnaeus’ genus was doubtless founded on Culex pipiens 
I have retained all those gnats in this genus which present the 
same squamose characters as that species. 
The characters of the genus Culex as here retained are as 
follows : palpi of the 9 short, three or four-jointed ; of the £ 
long, three-jointed ; constrictions at the bases may give the 9 a 
four or five-jointed and the £ a five-jointed appearance; the last 
joint in the 9 is usually large; the male may have the last two 
joints swollen, much as in Anopheles , or they may be narrower 
and the last pointed. The antennae, like those of the preceding 
genera, are pilose in the 9 5 plumose in the ^ , and are composed 
of fourteen joints'in the 9 ? fifteen in the £ , the last two in the 
male being long and thin. 
Head ornamented with narrow curved scales over the 
occiput, and upright forked scales especially thick on the back of 
the head, flat scales on the sides (Fig. 9, B); thorax with narrow 
curved hair-like or spindle-shaped scales; scutellum with narrow 
curved or spindle-shaped scales only ; abdomen with flat scales ; 
wings with small median scales to the veins and more or less thin 
linear lateral ones to some or all of the veins. In the wings the 
first sub-marginal cell is longer and narrower than the second 
posterior cell, and the posterior cross-vein is always nearer the 
base of the wing than the mid cross-vein. The scales may collect 
in certain areas and form spots ( C . annulatus), or the wing itself 
may be tinged ( C. mimeticus). The ungues of the 9 are equal, 
simple or uniserrated, of the £ unequal on the fore and mid 
legs, the larger uni- or biserrated, the smaller uniserrated or 
simple. 
The genus contains a large number of species, the essential 
characters being— 
(i) Short palpi in the 9 > long in the £ . 
(ii) Head with narrow curved and forked upright scales on 
the occiput only; never flat scales over the top of the head as 
in Stegomyia. 
