380 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



44. Pipiza femoralis Loew (Figs. 1, 3, 36, 72, 73, 74) 



Loew, Century, vi, No. 38, 1865; Williston, Synop. 

 N. Am. Syrph., p. 26 (and 28 albipilosa). 



Habitat: Ontario! Quebec, Ohio, Pennsylvania. A 

 medium sized, moderately pilose species, male usually 

 and female always, with two yellow spots forming an 

 arcuate band on second segment; hind femora with a 

 spinose area behind near end; face whitish pilose. 



Length, 8 to 9 mm. Male: Face and front shining, slightly metallic bluish 

 black, ground color slightly obscured by whitish pollen; face receding, white 

 pilose, sometimes with a few black hairs near the mouth and on the sides 

 above; front black pilose with white pile above and often on the sides. An- 

 tennae black, second joint often partly luteous, third usually yellow below 

 basally, in shape sub-cordate; arista brownish, its base sometimes lighter; 

 vertical triangle white pilose, a few dark hairs in front; post orbital pile white; 

 occipital cilia black; eyes with cinerescent pile. Thorax and scutellum shining 

 bluish black, white pilose, usually with a few black hairs on the humeri. 

 Abdomen shining bluish black, with sub-opaque areas as follows: one on second 

 segment, narrowed in middle and omitting the sides, an abbreviated fascia 

 on anterior margin of third and fourth segments and a similar fascia on apex 

 of third segment, widened in the middle so as almost to join the anterior 

 fascia; second segment with an interrupted yellow band terminating some 

 distance from the side margins; these spots vary in size and become obsolete 

 (var. albipilosa Will.) or sub-obsolete, appearing as yellowish patches in 

 certain lights, but they are never very large; their inner ends are truncate, 

 the outer more or less pointed, the longer side of the triangle formed by each 

 spot being in front. Pile white, moderately long, with shorter black pile on 

 the opaque areas except those on anterior half of second segment. Legs black; 

 hind femora incrassate, near end below bearing one or two rows of spinose 

 hairs; tips of all femora, anterior four tibiae and base of hind ones, and first 

 two joints of front four tarsi, yellow; front and middle tibiae with a piceous 

 band beyond middle, hind tibiae and basal two joints of their tarsi piceous; 

 apical three tarsal joints blackish. Wings faintly or moderately clouded with 

 brownish across middle, fading out apically and posteriorly, almost hyaline 

 in some specimens; stigma luteous. 



Female: Front slightly narrowed above, white pilose, with black pile im- 

 mediately above the base of the antennae and a few black hairs in front of the 

 ocelli; pollinose side spots broadly connected with side stripes of face, their 

 upper ends rounded. These spots leave a polished area between them about 

 \Yz times width of one spot. Spots on second segment broader and more 

 squarish than usual in male, with outer ends more rounded. Fifth segment 

 black pilose; tarsi lighter colored, mostly yellowish. Wings usually more 

 distinctly clouded. Pile sparser and shorter. 



Twenty specimens from various parts of Ontario. 



Very great confusion exists at present as regards the 

 identity of femoralis and f estiva, and I am not able 

 entirely to clear up the matter. So far as I know, the 

 only specimens of f estiva (?) which have been taken in 

 America, are females with much darkened wings; of 

 these I have taken several specimens. In 1914 Dr. 

 Williston determined for me two females as this species, 



