150 
A Monograph of Culicidae. 
laterally over the roots of the wings and on each side of the bare 
space in front of the scutellum; some of these bristles, especially 
those in front, have a yellowish tinge; scutellum ochraceous- 
brown, with narrow pale curved scales and seven median border 
bristles ; metanotum bright testaceous-brown ; pleurae pale 
testaceous-brown, with some dusky and frosty patches. 
Abdomen pale steely-brown when denuded, covered with 
fuscous to warm brownish scales, each segment with a basal band 
of yellow scales and with a row of pale posterior border-bristles ; 
the basal bands spread out laterally into paler lateral spots, con¬ 
tinuous with the bands; venter pale ochraceous, with pale scales. 
Legs pale yellowish, with fuscous scales ; coxae, bases, and 
venter of the femora pale yellowish ; apex of the femora, tibiae and 
tarsi brownish-fuscous, owing to the covering of scales ; femora, 
tibiae and metatarsi more or less bristly ; ungues equal and simple. 
Wings with brown scales of typical Culex form; first sub¬ 
marginal cell considerably longer and slightly narrower than the 
second posterior cell, its base considerably nearer the base of the 
wing than that of the second posterior cell, its stalk very short, 
about one-fifth the length of the cell, like C. pipiens, shorter than 
the stalk of the second posterior cell; stem of the second pos¬ 
terior cell not quite half the length of the cell ; middle and 
supernumerary cross-veins united, sometimes apparently , in one 
line, really at a very open angle; posterior cross-vein distant 
from the mid cross-vein from its own length to twice its own 
length. Halteres with a pale stem and fuscous knob. 
Length. —4 to 6 mm. 
Habitat .—Chares, Lower Amazon (Austen); Chili (Macq.) ; 
Brazil (Kollar) (?); South Provinces, Argentine (Blanch.) ; 
Uruguay (Walker) ; Argentine (Arribalzaga). 
Time of captures —February. 
Observations. —After examining a large number of South 
American mosquitoes, I have been obliged to assume that the 
species described by Macquart is a variable one, and hence none 
that I have seen exactly agree with either Arribalzaga’s descrip¬ 
tion of Macquart’s species or with what Giles states in reference 
to the type. 
The specimens I take to be this species, and from which this 
description is compiled, came from the Amazon region. 
The character which I think gives their identity is that the 
rufous thorax has two median parallel dushy lines. It cannot be 
confused with Culex faiigans, Wiedemann, because the thoracic 
