28 PROCEEDINGS OF THE NATIONAL MUSEUM vol. CG 



white pollen. All femora and tibiae yellow: posterior femora a 

 little blackened above at tip and hind tibiae only a very little darker 

 at extreme tip; hind basitarsus mostly yellow, even the base of 

 second joint a little yellowish. Wings about as in the male. 



Described from three males and four females which I took in 

 California in 1915 — one female at Los Cerritos, Los Angeles County, 

 April 3; one male and two females at Los Angeles, April 29; two 

 males at Los Angeles, May 3-4 ; and one female at Berkeley, May 8. 



Type.— M.2i\Q, Cat. No. 27046, U.S.N.M. 



22. ARGYRA SERICATA, new species 



Male. — Length, 4 mm. Face wide; face, front, and occiput cov- 

 ered with silvery white pollen. Palpi velvety black, with a little 

 white pollen. Antennae black, first joint with conspicuous hairs 

 above; second joint as long as wide; third joint as long as the basal 

 two taken together, obtuse at tip ; arista subapical, scarcely as long as 

 the antenna. Lower orbital cilia and beard white, longer below, the 

 short upper cilia black. 



Dorsum of thorax and the scutellum bright blue-green, with sil- 

 very white pollen, which is dense along the front and on the sides 

 of the dorsum; scutellum with two pairs of large marginal bristles 

 and a few small black hairs on the disk; pleurae more black, with 

 dense white pollen. Abdomen black, with bright green reflections, 

 especially on the anterior segments, the apical segment more purple ; 

 second segment with a large yellow spot on each side, which leaves 

 a rather broad hind margin and median stripe green; third with a 

 small, less distinct, yellow spot on each side in front; all hairs and 

 bristles on the abdomen black. Hypopygium (fig. 17) shining 

 black, the apical portion more testaceous; outer lamellae black, 

 pointed at tip, fringed with pale hairs ; the yellow inner appendages 

 are one clavate organ with two hairs and a pair of smooth, pointed 

 ones. 



Fore coxae yellow, with a blackish spot at base, their hairs and 

 bristles black; middle and hind coxae colored like the pleurae, their 

 tips yellow, each with two bristles on outer surface and a few black 

 hairs. Femora and tibiae yellow, with black hair; middle femora 

 with a row of moderately long black hairs below; posterior femora 

 with extreme tips brown, especially on upper surface; hind tibiae 

 black at tip for one-fifth their length; all the tibiae with only short 

 hair. Fore tarsi about one and one-fourth times as long as their 

 tibiae, their joints as 48-18-12-7-9 ; they are yellow, darker apically ; 

 middle tarsi black from the tip of the first joint, their joints as 

 G2-28-19-10-8 ; hind tarsi wholly black, their joints as 40-35-21- 

 12-10. Calypters yellow, with apical edge black and long yellow 

 cilia. Halteres yellow. 



