1042 APPENDIX 



rugose, pilose, black, with long coarse ciliation, the joints scarcely thickened at 

 the insertions of the whorls ; tori globose, with an apical excavation, ocherous, 

 with a dark brown spot on inner side. Clypeus large, convex, conical, pale 

 brown. Byes narrowed above, not contiguous, black with a green reflection. 

 Occiput with flat recumbent scales, black, brown below, the margins of the eyes 

 silvery white; erect forked scales on the nape dark; bristles along margins of 

 eyes coarse, long, black, directed forward. 



Prothoracic lobes well separated, moderately large, brown, with a narrow line 

 of pale violet scales and with a few black bristles. Mesonotum rather light 

 brown, the bristles forming dark median and subdorsal lines; clothed rather 

 sparsely with minute hair-like bronzy brown scales ; a short line of pale violet 

 ones on anterior angles of disk and another before roots of wings ; bristles coarse, 

 black. Scutellum with the median lobe large, lateral lobes prominent, each 

 lobe with a group of black setae. Postnotum yellow-brown, broad, nude, shining. 

 Pleurae brown, with small patches of violet scales ; coxae brown, sparsely black- 

 scaled. 



Abdomen cylindrical, blunt at tip ; dorsal vestiture black, bronzy at the bases 

 of the segments; a row of small, round, silvery white lateral spots, situated 

 basally on the segments; ventral vestiture of dirty white scales; marginal cilia 

 of segments abundant, dense, pale. 



Wings rather broad, hyaline ; second marginal cell moderate, a little shorter 

 than its petiole ; second posterior cell also shorter than its petiole ; basal cross- 

 vein about its own length from the anterior cross-vein; scales of veins black, 

 the outstanding ones long, ligulate. Halteres whitish, with dark knobs. 



Legs slender, rather long ; vestiture black ; femora silverv white below nearly 

 to tips. Claw formula, 0.0-0.0-0.0. 



Length : Body about 3 mm. ; wing 2.7 mm. 



Male. — Proboscis straight, moderately long, distinctly enlarged toward apex. 

 Palpi very short, slightly exceeding the clypeus. Antennae plumose, rather long, 

 the last two joints long and slender, rugose, brown, with long pile, the others 

 shorter, subcylindrical, with dark rings at the insertions of the hair-whorls. 

 Coloration similar to that of the female. Abdomen subcylindrical, rather more 

 slender than in the female, with many coarse bristles on the genitalia ; brown, 

 tips and sides of segments black, no white spots. Wings rather narrower than in 

 the female, the stems of the fork-cells longer, the second marginal cell being less 

 than half the length of its petiole ; vestiture sparser. Claw formula, 0.0-O.fr-O.O ; 

 one claw of the mid legs very large, the other of usual size. 



Length : Body about 3 mm. ; wing 2.3 mm. 



Genitalia: (Not microscopically prepared.) 



Pupa. — Cephalothoracic mass subpyriform, the abdomen slender, curved 

 around, the ends of the paddles reaching the prominence between the eyes. Air- 

 tubes rather long and slender, slightly expanded at tip, twisted at base, pale, 

 with a black central band. Hair-tufts small and fine, the pair at base of abdomen 

 feathery. Color luteous whitish, a dark gray stripe on dorsum of thorax and 

 abdomen ; eyes black. 



Eecently Doctor Dyar rediscovered the larvae in a pond near the mouth of the 

 San Diego Kiver and succeeded in rearing the adults. The larvae occurred in 

 the fringe of cat-tails and Lemna and as on the previous occasion were associated 

 with larvae of Anopheles and Culex. The larvae are fond of resting in an oblique 

 position, with the air-tube at the surface, the mouth holding to a root of Lemna 

 or other object. They remain perfectly quiet in this position for a long time. 

 They do not feed continuously, as with Culex, but feed rapidly along a root or 

 floating object or side of the receptacle, with a biting motion, then reassume the 

 position of rest. 



Old Town, San Diego, California, May 1, 1916 (H. G. Dyar). 



