PROCEEDINGS OF THE NATIONAL MUSEUM. 407 



opaque whitish poliinose, its i)ile or bristles aloug liind margins of the 

 segineuts h:>ng, blacik; hypopygiuni yellowish brown, very large, erect, 

 its pile black; central filament very robust, arcuate, free except toward 

 the apex, its extreme tip dilated. Legs slender, yellow, including the 

 coxie; on under side of hind femora before the apex is a low swelling, 

 in front of which is a robust, backwardly directed hook, while between 

 the swelling and the apex of the fennir on the inner side is a black 

 conical projection fringed near the base behind with one large and two 

 small teeth-like projections ; on the front and also on the hiud side of the 

 hind tibi;e near the base is a fringe of short black bristles, below which 

 on the inner side of the tibia is a conical projection, at which point the 

 tibia is rather suddenly bent outward; hind metatarsi slightly thicker, 

 but shorter, than the front ones. Halteres yellow. Wings grayish 

 hyaline, stigma and veins brown, a long bristle on costa near its base. 



Female. — Same as the male, except that the front is slightlj^ broader, 

 the abdomen blackish, light gray poliinose, and the hind legs simple, 

 but much thicker than the others. 



Ty2)es.—^os. 31S2 and 3183,U.S.is^.M.; length, 4 to 5 mm. Five 

 males and eight females, taken by the writer in March. 



Locality. — Southern California. 



EMPIS OTIOSA, new species. 



Male. — Head black, gray poliinose, eyes separated as widely as the 

 posterior ocelli, facets of a uniform size; antennoe black, third joint two 

 and one-half times as long as the first, rather narrow, style one-third as 

 long as the third joint; proboscis two and a half times as long as height 

 of head, palpi yellow. Thorax black, opaque gray poliinose, marked 

 with two darker vittte, its sparse pile and bristles black ; pleura black, 

 gray poliinose, its pile black; scutellum gray poliinose, bearing four 

 bristles. Abdomen black, depressed except toward the apex, sub- 

 shining, its pile rather abundant and long, black; hypopygium rather 

 small, middle lamella longer than the upper, rounded on the lower side; 

 filament slender, arcuate, yellow. Legs simple, very robust, femora 

 nearly twice as thick as their tibi;e, hind femora one-third longer than 

 the middle ones; coxa? black, femora dark brown, yellowish at base and 

 apex, the hind ones sometimes wholly yellowish, tibial and tarsi light 

 yellow, apex of the latter brown ; front metatarsi unusually large, nearly 

 twice as long and as thick as the middle ones, one-half thicker and one- 

 third longer than the hind metatarsi. Knob of halteres light yellow. 

 Wings hyaline, stigma pale brownish, veins dark brown. 



Female. — Same as the male, except that the tibiae and tarsi are 

 darker, the yellow being replaced with reddish; the femora are usually 

 reddish and are more slender; the hind ones are nearly twice as long 

 as the middle ones; front metatarsi more slender and one-half longer 

 than the middle ones, also more slender and slightly longer than the 

 hind ones ; wings brownish gray. 



