48 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 30 Ser. 



1. Fifth joint of fore tarsi with a projection below 2 



Fifth joint of fore tarsi without a projection 3 



2. Fore tibiae with a row of stubby bristles similis Ald. 



Fore tibiae without a row of stubby bristles falco Ald. 



3. Fourth vein ending before the tip of the wing 4 



Fourth vein ending in the tip of the wing 5 



4. Third joint of hind tarsi shorter than the fourth. 



tertianus Loew. 

 Third joint of hind tarsi longer than the fourth. 



■marcidus, sp. nov. 



5. Pulvilli of fore tarsi enlarged 6 



Pulvilli of fore tarsi not enlarged lineatus Loew. 



6. Middle tarsi plain cuprinus, sp. nov. 



Fourth and fifth joints of middle tarsi dilated pugU, sp. nov. 



47. Sympycnus marcidus, sp. nov. 



Plate IV, Figs. 92-95. 



Male. Length 2.5-3 mm.; length of wing 2.5 mm. Proboscis very small, 

 retracted, piceous; palpi minute, yellowish. Face very narrow, covered 

 with white dust, the eyes almost meeting in dried specimens. Antennae very 

 small, black; first and second joints short, of the usual form; third joint as 

 long as broad, terminating in a broad, blunt point covered with conspicuous 

 pile; arista inserted dorsally, tapering, pubescent. Front bronze black. 

 Postocular cilia white. Thorax and scutellum dull metallic green, dusted 

 with white, the former with an indistinct black vitta down the middle. Pre- 

 scutellar depression distinct, but short. Abdomen metallic green, more cup- 

 reous dorsally and posteriorly, dusted with white along the sides; venter 

 yellowish. Hypopygium shining black, subglobose, with a pair of relatively 

 long, straight, pale appendages projecting downward. Pleurae dull metallic 

 green, covered with gray dust; metapleurae yellowish. Coxae yellow; mid- 

 dle and hind pairs infuscated on their outer surfaces; fore pair covered with 

 distinct white hairs. Legs yellow, blackened from the tip of the first tarsal 

 joint; fore tibiffi not incrassated, without bristles; fore tarsi considerably 

 shorter than the fore tibiae; first joint as long as the four succeeding joints 

 taken together; the latter subequal; fifth joint broadened, with distinctly 

 enlarged white pulvilli. Middle legs slender; tibia with four or five conspic- 

 uous black bristles scattered along the outer surface; middle tarsi nearly as 

 long as the tibiae. Hind tarsi somewhat compressed from side to side, joints 

 gradually decreasing in length and thickness to the tip; third joint bearing 

 on its outer upper edge a series of long bristles; the most distal of which is 

 strongest and distinctly geniculate; fourth joint with a few peculiar erect 

 bristles on its outer surface. Hind tibiae and tips of hind femora brownish 

 in many specimens. Wings grayish hyaline, narrowed towards the base. 

 Third vein ending very near, but distinctly in front of the tip of the wing; 



