448 MOSQUITOES OF NORTH AMEEICA 



Larva, Stage IV (plate 111, fig. 377). Head rounded, transverse, sides 

 bulging, widest before eyes. Antennae long, rather slender, nearly smooth, a 

 large tuft situated l)eyond basal two-thirds and arising from a slight notch. 

 Upper pair of dorsal head-hairs triple,' lower pair single, ante-antennal tufts in 

 fours. Lateral abdominal hairs in fours after second segment; lateral comb of 

 eighth segment of many spines in an irregularly triangular patch. Air-tube 

 very long and slender, twelve times as long as wide, a little flared at base, then 

 straight and uniform, without hairs ; terminal hooks small ; pecten of about ten 

 teeth, the outer ones long, sparse. Anal segment slender, much longer than 

 wide, ringed by the plate; dorsal tuft of two very long hairs on each side; 

 ventral brush well developed, confined by the chitinous ring. Anal gills equal, 

 longer than the segment, bluntly pointed. 



The larvas live in the water between the leaves of Bromeliacese. 



Trinidad to Brazil. 



Trinidad, April 11, 1905 (F. W. Urich). The species is reported also from 

 Sao Paulo and Para, Brazil (Theobald, Bourroul). 



Culex ocellatus is a highly specialized form of the group of Culex breeding 

 in water-bearing Bromeliaceae. Its relationship with such forms as C. imitator 

 and C. pleuristriatus is obvious, not only in the general characteristics, but in 

 the dark pleural stripes. In addition, C. ocellatus shows a strong, white, prui- 

 nose transverse bar on the upper half of the pleurae, reminding one of the 

 pleural markings of Carrollia iridescens. Other closely related species are 

 Culex conservator, C. corrigani and C. hisulcatus; the first two of these show 

 dark, diffuse, integumental spots over the roots of the wings, and all of them 

 show their relationship in the structure of the male genitalia, and in the larval 

 characters. In C. ocellatus, there is a shortening of the male palpi, leading up 

 to the greater reduction in the three species mentioned. 



CULEX GRAVITATOR Dyar & Knab. 

 Culex gravitator Dyar & Knab, Journ. N. Y. Ent. Soc, xiv, 207, 218, 1906. 



Original Description of Ctxlex gravitator : 



Antennse with the tuft before the outer third, dark; hairs single; body glabrous; 

 lateral hairs in threes on abdominal segments 3 to 6; tracheal tubes narrow, angu- 

 lated within the segments. Air tube six-and-a-half times as long as wide, with long 

 pecten reaching to one-third. Anal gills small. 



Collected by the junior author in a large Bromeliaceous plant containing water 

 between the leaves, growing in a thicket in a valley above Cordoba, Mexico. In spite 

 of careful attention no adults were bred. Some of the larvee lived two months after 

 being collected; they probably died of starvation. 



The following is an abstract of the table : 



1. Antennaj with the tuft outwardly placed, the part beyond slender. . 5 



5. Air tube four times as long as wide or over 7 



7. Anal appendages four, normal 8 



8. Air tube with four to ten paired tufts along the posterior line in a 



straight row, none displaced, or the hairs obsolete or absent. 18 



18. Air tube without a crown of spikes, smooth throughout 19 



19. Air tube with long well-defined tufts 20 



20. Body glabrous or lightly granular 26 



26. Air tube regularly tapered, the tip not widened 28 



28. Both head hairs single gravitator 



Description of Larva of Cuxex gravitator (Aditlt Unknown) : 



Larva, Stage IV (plate 105, fig. 350). Head rounded, widest through eyes, 

 a large notch at insertion of antennae, front margin arcuate. Antennae large, 

 slightly curved, basal two-thirds thick and well spined, a large tuft from a 

 notch ; two long set^e nearly at tip, a long seta, a short one and a digit at tip. 

 Both pairs of dorsal head-hairs single, ante-antennal tuft multiple. Mental 



