222 Annals Entomological Society of America [Vol. X, 



border. Abdominal spots distinctly yellowish-white, those on the 

 second segments transverse, and reaching the lateral margin. The 

 spots on segments three and four arcuate, attenuated at their tips, and 

 reach the lateral margin anteriorly, venter very pale yellow. Legs 

 yellowish, with white pile, bases of femora black; wings hyaline. 



Habitat: Three specimens (9), Grand Junction, Fort 

 Collins, Colorado. G. P. Weldon, Collector, August 14, 1909. 



Syrphus flukei n. sp. 



Length S mm. Face bluish yellow, only slightly pollinose, a bluish 

 median stripe from roots of antennae to oral margin. Oral margin 

 brownish, shining; cheeks black, opaque, front dusky yellowish with 

 yellow pile; frontal triangle slightly prominent, whitish pollinose, with 

 black pile. Antennae brownish red, a dash of wine red at roots of each, 

 and light yellow lines running obliquely from them; third joint ovate, 

 yellowish at base; arista brown, bare; eyes bare, contiguous; thorax 

 shining metallic greenish yellow, with yellowish pile, dorsum with 

 ramifying fern-like ferruginous markings, darker on margins, scutellum 

 yellowish, clearer on margin, semi-translucent, covered with rather 

 abundant long white pile. 



Abdomen black, chiefly opaque, with three pairs of yellowish 

 arcuate cross-bands, all reaching the margin; first segment wholly 

 shining. Posterior margins of segments three, four and five, shining; 

 first pair of abdominal spots semi-ovate with attenuated tips which 

 reach the lateral margin only at extreme apex of the first third of seg- 

 ment, second and third pairs distinctly arcuate, with attenuated tips 

 reaching lateral margin at junction of segments, inner angles extending 

 forward and rounded, fourth segment with a narrow yellowish hind 

 margin. vSegment five entirely yellow. Legs brownish yellow; femora 

 with rather long yellowish pile, base black, tarsus and metatarsus 

 brownish. Wings hyaline, sub-costal cell brownish, stigma distinctly 

 3'ellowish. 



Habitat: One specimen, Fort Collins, Colorado, May 7, 

 1915. On plum blossom. Chas. Fluke, Collector. 



Syrphus marginatus n. sp. 



Length, male, 12 mm. Face yellow with a shght bluish tinge, 

 shining, a brown median stripe from oral margin not reaching the 

 antennas; cheeks bluish black, shining, the oral margin anteriorly, 

 connecting under the oral opening with the color on the opposite 

 side; frontal triangle yellow, with black pile, greyish pollinose; a slender 

 black or brownish arch above the base of the antennae; vertical triangle 

 small, metallic blue, with black pile; antennae brown, along the under- 

 side more or less reddish, first two joints lighter than the third; third 

 joint oval; eyes bare; thorax metallic green with moderately thick 

 light pile; scutellum translucent yellowish, shining, with bluish 

 opalescent reflection, chiefly light pile. Abdomen black, principally 

 shining, with three pairs of yellow spots. The first pair transverse, 



