254 MOSQUITOES OP NORTH AMERICA 



CULEX MORTIFICATOR Dyar & Knab. 

 Culex mortificator Dyar & Knab, Journ. N. Y. Ent. Soc, xiv, 206, 210, 1906. 

 OEiGiNix DEscBXPTiorr OF Culex moktificatob: 



Antennae normal, dark throughout; head hairs in threes. Air tube seven times 

 as long as wide, uniformly slightly tapering, the pecten on the basal fourth; tufts 

 very long but few-haired. Comb of the eighth segment of many long spIne-llke scales 

 in a large patch. Anal segment rather long, normal; anal gills unusually long. 



Collected by the junior author in Zent, Costa Rica, in a hollow in a stump of a 

 banana tree, but no adults were obtained. 



The following is an abstract of the table : 



1. Antennae 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 three paired tufts posteriorly outwardly, the middle 



one moved laterad out of line, usually situated near or not much 

 beyond the middle of the tube 9 



9. Body glabrous; air tube 7X1; antennae dark mortificator 



Desceiption of Laeva of Citlex mobtificatoe (AnrrLT Unknown) : 



Larva, Stage IV (plate 97, fig. 316). — Head rounded, widest through eyes, 

 bulging on sides, a large notch at insertion of antennae; front margin arcuate. 

 Antennse long, a little curved, spined; a large tuft beyond outer third; three 

 long spines, a short one and a digit on a pedicel at tip. Both dorsal head-tufts 

 in threes, long, the ante-antennal tufts multiple. Mental plate triangular with 

 straight sides ; a large central tooth and ten on each side, the eighth long and 

 projecting, the last two small. Mandible quadrangular ; two long filaments and 

 a tuft of long hafrs before tip; an outer row of cilia from a collar; a row of 

 curved processes on the front margin, each bearing a long hair and some short 

 ones ; dentition of four teeth on a process, the first long, the third small ; a double 

 tooth at base, a long serrate filament and a row of six feathered hairs within; 

 process below thick, curved, obscurely furcate, a longitudinal and a transverse 

 row of hairs, followed by a tuft at tip of outer limb ; basal angle slight, a row 

 of stout hairs within ; a row of hairs at base. Maxilla elongate, conical, divided 

 by a suture ; inner half with a row of stout hairs along margin, some of the basal 

 ones feathered ; two rows of cilia within ; a row of long hairs at tip running down 

 along the suture ; outer half with two large filaments at the middle, a spine on 

 the other side, and some very slight dentations on the margin. Palpus small, 

 rather slender, with four slender irregular apical digits. Thorax rounded, wider 

 than long; abdomen moderate, the anterior segments shorter; skin smooth; 

 lateral abdominal hairs in pairs after the second segment. Air-tube very long, 

 nearly straight, slightly and gradually tapered, seven times as long as wide; 

 pecten reachiag one-fifth of tube; single tooth broad and short, with six 

 branches; a long double tuft just beyond the pecten, another on the side at 

 middle of tube and a small subapical tuft. Lateral comb of eighth segment of 

 many spines in a large triangular patch ; single spine elongate, widened at tip, 

 fringed with spinules. Anal segment longer than wide, ringed by the plate ; 

 dorsal tuft a group of long hairs on each side; a single lateral hair; ventral 

 brush well developed, confined to the barred area, ventrally situated. Anal 

 gills very long, three times as long as the segment, uniformly tapered. 



The larvse live in water in hollow trees. Mr. Knab obtained them in the 

 hollow in a stump of a banana-tree containing a dark-brown liquid. 



Costa Eica. 



Zent, 20 miles from Port Limon, September 26, 1905 (P. Knab). 



These larvse were met with by our collectors only once, and died in transit 

 from the collecting-ground, so that no adults have been reared. 



