CULEX PALUS 343 



Origixal Description of Culex palus: 



Thorax reddish-brown, with traces of dusky lines; pleurae ochraceous. Abdomen 

 dusky-brown, with narrow basal grey bands, last segment unhanded; venter grey. 

 Legs brown, unhanded; venter and base of femora grey; knee-spot and apex of hind 

 tibite grey. Wings of $ with similar venation to fntigans. Male palpi black, traces 

 of one pale basal band only. 



$. Head brown, with very small narrow-curved dull golden scales and black up- 

 right forked scales on the occiput, small flat greyish-white ones on the sides of the 

 head; antennae, palpi, and proboscis deep brown, the palpi with short pale golden 

 hairs. 



Thorax reddish-brown, with scanty small bronzy-brown, thin narrow-curved scales 

 and dark brown bristles, which show more or less clearly in lines; scutellum paler 

 brown, with thin narrow curved bronzy-brown scales; metanotum deep chestnut- 

 brown; pleurae pale, ashy-grey. 



Abdomen pallid, covered more or less scantily with flat dusky-brown scales, narrow 

 basal bands of white scales and brown border-bristles, the last two segments with the 

 banding not so prominent; the basal white-scaled bands look more prominent than 

 they really are, owing to the few scales present allowing the pale integument to shine 

 through; venter pallid. 



Legs brown; coxae, base, and venter of femora pale grey; the knee-spot and tibio- 

 metatarsal joint pale, owing to an absence of scales; ungues small, equal and simple. 



Wings with typical brown Culex scales; first sub-marginal cell longer and nar- 

 rower than the second posterior cell, its base a little nearer the base of the wing, the 

 cell about two and a half times the length of the stem; second posterior cell about 

 one and a half times the length of its stem; posterior cross-vein about two and a half 

 times its own length distant from the mid. Halteres pale ochraceous. 



Length. 3 to 3.7 mm. 



(^. Darker than the $. Palpi brown; apical joints deep black, with black hairs, a 

 trace of pale banding on the ante-penultimate segment. 



Antennae with deep brown plume-hairs; proboscis brown, with long brown hairs 

 beneath about the middle of its length. 



Thorax as in the $; metanotum and pleurae pale. 



Abdomen deep blackish-brown, with five prominent basal white bands, the last two 

 spreading out laterally. 



Legs brown; coxae, venter of femora, and their base pale grey; a prominent yellow 

 spot at the tibio-metatarsal joint; fore and mid ungues unequal, both uniserrated; 

 the tooth of the larger in the fore pair much bent downwards. 



Wings with the first sub-marginal cell longer and narrower than the second pos- 

 terior cell, their bases nearly level; stem of the former equal to nearly half the 

 length of the cell, stem of the latter nearly as long as the cell; posterior cross-vein not 

 quite twice its own length distant from the mid cross-vein; scales on the branches of 

 the first fork-cell rather thick. 



Length. 3.5 to 4 mm. 



Habitat. St. Vincent, Barbardos (Dr. Low). 



Time of appearance. June (Barbardos). 



Observations. Described from a single female and several males bred by Dr. Low. 

 The larvae were obtained in a swamp at Barbados, and in a marsh behind Kings- 

 town, St. Vincent. It is a very small delicate Culex, very like C. nigritiilus, Zetter- 

 stedt, but clearly distinct, yet by means of a hand-lens the only difference is seen in 

 the J' palpi of nigritulus being banded with two bands. The scale structure of the 

 thorax is, however, different: in this species the scales are very thin, narrow, and 

 curved, and deep bronzy-brown. 



There are no specimens that we have been able to identify with this species in 

 the collection of the U. S. National Museum. It is highly probable that the 

 specimen from British Guiana, described by Theobald as the male of this species 

 (Mon. Culic, iv, 456, 1910) belongs to a different species. The localities are 

 remote and in males the vestiture is usually so defective that they can not be as- 

 sociated with any certainty on superficial characters. 



This may be the same as Cidcx siinili.'^ Theobald. Mr. F. W. Edwards, of the 

 British Museum, is of this opinion and we consider it highly probable. Theo- 

 bald's comparison with C. nigritulus (sense of Theobald, not Zetterstedt) and 

 his indication of minute sparse scales on the thorax certainly point in this direc- 

 tion, as C. similis is the only species with this character that we know from the 

 West Indies. Theobald's type was evidently a much abraded specimen. 



