AEDES TRI8EKIATUS 765 



lobe. Clasp-filament small, slender, with a long articulated terminal spine nearly 

 half as long as filament. Harpes elliptical, concave, inner margin thickened and 

 revolnte, tip pointed and recurved. Harpagones with a stout columnar base 

 which has a blunt projection in the middle and is minutely pilose and with a 

 long slenderly ligulate articulated filament, longer than the stem and pointed at 

 the tip. Unci approximate, revolute, forming a small basal cylinder. Basal 

 appendages undeveloped. 



Larva, Stage IV (see figure of the entire lai-va, plate 74). — Head rounded, 

 narrowing slightly before eyes, front margin broadly arcuate. Antennae long, 

 cylindrical, slender, smooth, a single hair a little before the middle ; four setae 

 of various lengths at tip and a digit on a pedestal. Byes large, transverse, 

 bluntly pointed. Upper pair of dorsal hairs single, lower pair double, ante- 

 antennal tuft multiple. Mental plate triangular, rather small; central tooth 

 large, nine side teeth more remotely spaced toward base. Mandible quadrangu- 

 lar, outer edge straight, a patch of short spines near base ; two filaments toward 

 tip from a distinct notch; an outer row of cilia from a collar; twelve filaments 

 on outer edge; dentition of four teeth on a process, the first longest, a curved 

 tooth before, two little forked ones at base ; process below furcate, with groups 

 of hairs and a long row down to below base ; five hairs within, three long ones 

 below base ; lower angle small ; six stout long hairs toward baseT Maxilla conical, 

 elongate, divided by a suture ; inner half with hairs which are coarse inwardly, 

 a small tuft at tip; outer half with a group of hairs and some small spines, two 

 filaments near the suture ; palpus small with four digits at tip. Mouth-brushes 

 moderate, normal. Thorax rounded, wider than long; hairs rather abundant, 

 rather short, the anterior prothoraeic tufts well developed. Abdomen stout, 

 rather long, the anterior segments short and transverse; hairs moderate, the 

 laterals of first two segments multiple, those of second to sixth segments double, 

 long ; many short secondary hairs and distinct tufts; tracheal tubes broad. Air- 

 tube stout, subcylindrical, the tip rather bluntly rounded, about two and a half 

 times as long as wide; pecten reaching to middle of tube, uniform, dense, the 

 spines long, wider at base ; a single hair beyond the pecten. Lateral comb of 

 eighth segment of few scales in a partly double row; single scale elongate, 

 tapering, fringed throughout with small spines, without larger terminal one. 

 Anal segment as wide as long, dorsal plate reaching near ventral line; dorsal 

 tuft a long hair and brush on each side ; a rather large lateral tuft at angle of 

 plate ; ventral brush well developed, of loose long-stemmed tufts, extending well 

 toward base. Anal gills long, stout, sack-shaped, bluntly rounded. 



Pupa (plate 149, fig. 708) . — Thoracic mass heavy, pyriform ; air-tubes small, 

 slightly expanded. Abdomen relatively rather slender ; a dorsal fan-shaped tuft 

 on the first segment ; hairs rather numerous toward posterior margins of seg- 

 ments ; a double hair at posterior angles of seventh segment, a tuft at poste- 

 rior angles of eighth segment. Anal paddles ovate, with a stout terminal bristle. 



Egg (plate 146, fig. 676). — Fusiform, flattened on one side, the micropylar 

 end more bluntly rounded than the other, with a gelatinous cushion ; sculpture 

 regularly hexagonal ; color black. 



The larvae live normally in the water in holes in the trunks of trees ; occasion- 

 ally they frequent artificial receptacles in wooded situations, more particularly 

 those made of wood. The eggs are laid upon the sides of the cavity, just above 

 the water line, singly or in groups of two to five, with the long diameter upright, 

 attached firmly to the surface. As the water dries, the eggs remain, and when not 

 wet with water that season, or if late in the season whether dry or wet, hibernate. 

 When covered with water the eggs hatch. There are probably several broods 

 during the season, though this has not been determined. The appearance of 

 female adults all through the summer may be due to the successive developments 



