86 BULLETIN 31, UNITED STATES NATIONAL MUSEUM. 



on the other, a well defined triangle above the antennai; the sides 

 of this arch run down alonsjthe eyes and (toalesce with the facial pollen; 

 anteiiiKB inserted on browuisli-ycllow ground; thorax bluish green; 

 scutelliiin dull yellow, brown at the extreme ends on each side; it sel- 

 dom shows any trace of a bluish metallic reflection ; the four front legs 

 are reddish yellow, femora b.lack at base ; tibii3e with a trace of a brown- 

 ish ring; tarsi brownish. The abdominal cross-bands usually reach the 

 lateral margins of the segments, but quite often they stop a little dis- 

 tance before, leaving a narrow black border between ; their color is red- 

 ish or ])ure yellow, with a more or less distinct whitish pollen, which 

 often gives them a whitish appearance. 



Male. — The face often, not always, has a more distinct metallic bluish 

 reflection ; the oral border is more often bordered with brown here than 

 in the female ; the ground color of the abdomen is more opaque. 



I compared twenty-five males and sixty-five females, mostly taken 

 by "Sir. Morrison in the White Mountains, New Hampshire." — Osten 

 Sacken, 1. c. 



Several specimens from the White Mountains agree very well with 

 the foregoing description of Baron Osten Sacken. A single female from 

 Arizona does not show any appreciable difference. 



Syrphus zauthostomus, u. sp. 

 Habitat. — Pennsylvania ! 



$ . Length, 11 to 12'"°^. Face and cheeks wholly yellow, antennae 

 reddish yellow, the third joint somewhat brownish above, but little 

 longer than wide, the arista black. Frontal triangle with a small black 

 spot in the middle, gray pollinose along the eyes, black pilose in the 

 middle. Dorsum of thorax shining metallic green, with light colored 

 pile. Scutellum wholly yellow. Abdomen black, but little shining, the 

 three principal bands very broad, attaining the lateral margins in their 

 full width ; first band interrupted, the spots narrowly separated, with 

 their inner ends rounded; second and third bands with a narrow but 

 deep emargination in the middle behind ; fifth and sixth segments with 

 a yellow hind margin. The black forms narrower bands than the yellow, 

 and does not quite reach the margin. Legs yellow, the tip of hind tibiae 

 and their tarsi brownish. Wings hyaline, the stigma yellowish. 



$ . Front metallic green, yellow below, on the lower half with yel- 

 lowish pollen. Yellow spots of the second abdominal segment larger, 

 more nearly square, and only narrowly separated. 

 Two si)ecimens, Pennsylvania (Mr. Keen). 



Syrphus genualis, ii. sp. 



JIahitat. — New nami)shirc! 



?. Length, 7.5""». Front shining black, with an interrupted band 

 of whitish ])ollen across the middle. xVntennaj yellowish red, the third 

 joint brownish above. Face yellow, a median strii)e, the oral margin 

 and the cheeks, deep shining black. Dorsum of thorax shining metal- 



