BIOLOGY OF PHILIPPINE CULICID.13. 243 



are always abundant in regions near forests. They are vicious biters 

 and inflict a very painful sting, which lasts several hours. They occa- 

 sionally enter houses. 



Stegomyia persistans Banks. 



Stegomyia fasciata persistans Banks, FMUp. Journ. 8ci. (1906), 1, 984, 996. 



Egg: The egg of this species measures 0.75 millimeter in length. It is a long, 

 slender oval, slightly blunt at one extremity. It is a light gray when laid, but 

 within a very short time turns jet-black. ,The surface is very finely reticulated. 



The eggs are laid singly at the water line upon the sides of vessels in 

 and around houses, most frequently in receptacles containing rain water. 



The period of incubation is twenty-four to foi-ty-eight hours according 

 to the temperature. 



Larva: The larva upon emerging measures 1.2 millimeters and is light graj^, 

 with the exception of the head which is brown-gray. 



The larval period lasts seven to ten days, during which the greatest growth is 

 made in the first five days. 



The full-grown larva measures 10 millimeters in length and is most readily 

 distinguished by the color of the respiratory siphon, which is dark chestnut- 

 brown. 



The body segments, including those of tlie thorax, are very pale and semi- 

 transparent. They are sparsely clad with setae, the three lateral groups on each 

 side of the thorax consisting of from eiglit to sixteen setse each. The pseudopoda 

 on the latero-ventral area are well defined, the ungues of the middle and posterior 

 pair being prehensile, while the anterior pair have none. Small chitinous 

 sclerites mark the position of the mid and posterior dorso-lateral pairs of setae. 



Quadrifid bristles grow from the dorso-lateral area of the first three abdominal 

 segments and dorsal to these are very short trifid seta;. 



The remaining abdominal segments have long, lateral, trifid or simple bristles 

 and simple to quadrifid setae of very small size on their posterior areas. 



The lateral comb of the eighth seginent consists of ten comb scales, dorsad, 

 ventrad, and caudad of which on each side is a quadrifid seta. The pecten 

 scales are fourteen in number with a quadrifid bristle on the air tube at their 

 apical limit. 



The lateral comb of the eighth segment consists of ten scales, dorsad and 

 ventrad to which on each side is a quadrifid seta; posterior to the middle of 

 the comb on the margin of the segment is a long quinquiefid, pectinate bristle. 



The general appearance of the ninth segment is like that of Worcesteria grata 

 Banks, the chitinous sclerite covering nearly the whole segment. From the 

 posterior dorsal margin grow the dorsal anchor bristles to the number of six. 

 These are twice the length of the anal tracheal gills ("anal fins" of Theobald) 

 which, in turn are twice as long as the ninth segment. 



The larvs of this species may be distinguished from those of Stegomyia 

 samwensis Ludl., by the latter having the surface of the anal tracheal gills 

 covered with minute, regularly placed annular spots. In S. persistans Banks, 

 the tracheae in these gills are 4- or 5-branched. 



Ventrad to the tracheal gills, on the posterior margin of the ninth segment, 

 are the twelve ventral anchor bristles of the same length as the dorsal, but less 

 curved than they. 



