snow: syrphidae. 35 



however, better than elsewhere. In one specimen, the second joint of 

 the antennae is shorter than the fir^t, and only one-fourth the length 

 of the third. In five examples the second abdominal cross-band is not 

 interrupted ; in the others it is distinctly parted. In two, the: third 

 band does not reach the yellow of the broad hind margin ; in two 

 others it barely touches it; in five, the two bands broadly coalesce. 

 The yellow of the fifth segment, in four specimens, incloses a black, 

 inverted V; in two others an inverted Y. 

 Paragus bicolor Fabr. 



Three specimens, Colorado. These may be located under Schiner's 

 variety taeniatus. 



Melanostoma stegnura Say. 



Si/rphus stegnu.s Say, Journ. Acad. Phil, vi, p. KiH. 



Melanostoma tigrina Ostpu Sacken, AVcsLern Diptera, p. 323. 



Melanostoma stegnum/\N\\V\?,%on, Biol. Centr.-Amer. Diptera, iii, p. 10. 

 Eleven specimens, Colorado, which answer well to the descriptions. 

 The metallic band of the fourth abdominal segment is sometimes in- 

 terrupted, and there is usually a triangular opaque black spot near the 

 anterior border of the fifth segment. "The female, hitherto unknown, 

 has the front broad above, pollinose, except on the upper part, and 

 with black pile; the thorax more shining metallic blue; the tibiae 

 yellow, and on the third and fourth abdominal segments there is a 

 narrow shining stripe, bisecting the black, as in the fourth segment of 

 the male. The male has some long black hairs on the outer side of 

 the front and middle tibiae, which are inconspicuous in the female. 

 It is evident, from the lighter color of the tibiae, that Say's specimens 

 were females." Williston, 1. c. 



Melanostoma mellinum Linnc 



A single female specimen from Manitou Park. 



Melanostoraa, n. sp. ? 



Male. Face and front dark metallic blue, shining, thinly covered 

 with light-colored pollen; tubercle and epistoma black, shining, the 

 former small. Antennae black, third joint yellowish red below, 

 oblong. Pile of frontal and vertical triangles dusky. Thorax bronze- 

 black, shining, sometimes bluish black, the pubescence white. Hal- 

 teres yellowish. Abdomen long and narrow, with almost parallel 

 sides; first segment metallic blue, shining; second segment opaque, 

 or subopaque, black, with a light metallescent scallop on the sides, 

 reaching to the distal third bf the segment ; third and fourth segments 

 similar, marked anteriorly by a wide, interrupted, or subinterrupted 

 blue fascia, deeply and widely emarginated, or concave behind ; hind 

 border of the third, and sometimes of the second segment, narrowly 

 brown; fifth segment and the hypopygium metallic bluish green ; sides 



