SYNOPSIS OF NORTH AMERICAN SYRPHID^. 293 



Entieiemeut d'uu uoir luisaut, bri^veinent clairseine d'un duvet 

 grisatre; ch^te, face, yeux, uus; cuillerons blaucs, balanciers testacies; 

 ailes un peu jauuatres; quelques inacrochetes noirs au bord de l'6cus- 

 8on. — 1 specim. — Bigot, /. c. 



Chilosia tristis. 



I am wroDg iu uniting the male and female specimens described under 

 C. pallipes. Notwithstanding the fact that specimens were collected 

 together, almost indeed at the same moment, they belong, I believe, to 

 different species. My reasons I find in the shape of the first posterior 

 cell. In C. tristis (the males) it is broader, and the last section of the 

 fourth vein comparatively longer than iu C. pallipes (the females). The 

 female of C. tristis, according to Loew, diflers also, apparently, in not 

 having the light-colored humeri. 



SYRPHUS. 



Syrphus fumipennis. 



Syrphus fumipetmis Thomson, Eugenics resa, 499. 



Habitat. — California (Thomson). 



$ . Length, 10™™. Eyes bare, frontal triangle fuscous pilose, yellow- 

 ish; face slightly concave below the autennse, yellowish-white; cheeks 

 bronze fuscous, subopaque; the lateral and front oral margin blackish, 

 shining. Antennae yellow. Thorax bronze fuscous, the sides more 

 yellowish; pile pallid; scutellum pallid testaceous, with fuscous and 

 pallid pile intermixed. Wings somewhat smoky. Abdomen oval, sub- 

 depressed; short, pallid pubescent; second segment deep black, long 

 yellow pilose on the sides, with a yellow, triangularly oval spot on each 

 side, the sides anteriorly confluent with the margin; third and fourth 

 segments deep black, with a broad yellow posteriorly sinuate fascia; 

 hind margin of the fourth and fifth segments testaceous; hypopygium 

 shining black. Legs yellow, base of the femora black fuscous. 



The above is an abstract of Thomson's very long and redundant Latin 

 description. He says of the species, that is is very similar to *S'. coroUa\ 

 but differs in the smoky wings and abdominal bands. I cannot apply 

 the description to any species which I know, though I think it comes 

 nearest to Americanus. The legs are said to be black only at the base 

 of the femora, and the bands of the third and fourth abdominal seg- 

 ments are not stated to reach the margin. 



Syrphus ochrostoma. 



Syrphus ochrostoma Zetterstedt, Dipt. Scand., viii. 3133; Schiner, Fanna Auatr., 

 i, 310; V. d. Wnlp, Tijdschr. v. Ent., xxv, 134. 



Habitat. — Europe, Canada (v. d. Wulp). 



5,2. Length, 12™™, Is like *S'. ribesii, but the scutellum is yellow 

 pilose, and the femora are wholly yellow. 



