SYNOPSIS OF NORTH AMERICAN SYRPHIDiE. 163 



^ , 9 . Leiiji'tli, 10 to 13™™. Face densely clothed with whitish pol- 

 len and pile, when denuded the ground color somewhat reddish, in the 

 middle with a large oval shining spot on the tubercle, and the cheeks 

 also, shining black ; in profile concave below the antennae, the tubercle 

 large. AntennsB black, the third joint a little brownish or reddish ; 

 arista reddish, very briefly pilose near the base. Front in female 

 clothed with yellowish-whitish ])olleu and pile, leaving a median stripe 

 brown ; on the upper part a small vittula in the middle, a larger oval 

 spot near the eyes, and theocellar spot, black with black pile. Eyes pilose 

 on the upper part; frontal triangle not much longer than the suture 

 between the male's eyes, a little shining in the middle. Thorax with 

 short, not abundant, light colored i)ile; shining greenish black with two 

 or three indistinct, somewhat opaque stripes. Scutellum yellowish; 

 pile mostly blackish above, yellowish on the border. Pleurae with more 

 abundant yellowish pile. Abdomen shining greenish black ; the usual 

 triangular spots on the second segment sometimes yellowish, usually 

 metallic shining, not contiguous in the middle, elsewhere the color is 

 opaque velvety black with a shining metallic spot in the middle behind; 

 third segment with three opaque spots, an elongate one on each side 

 behind, and an oval median one in front, sometimes there is a yellow- 

 ish spot on the sides ; fourth segment with an oval median opaque spot 

 in front ; hind margin of the second, third, and fourth segments yel- 

 low, sometimes nearly obsolete; pile very short, on the first segment 

 longer, whitish, on the opaque portion black, elsewhere more yellowish. 

 Legs black; basal portion of all the tibiae yellowish white. Wings 

 hyaline, small stigmatic spot brown, a brownish tint often near the mid- 

 dle of the wing. 



Fifteen specimens, Connecticut, District of Columbia (Patton), White 

 Mountains (Dimmock, 1447), Kansas. 



About the synonymy of L'Herminieri and chalybeus there can be no 

 doubt, the descriptions agree perfectly, and Osten Sacken, who ex- 

 amined the types, pronounced them to be the same. E. niger and in- 

 cisuralis of the same author differ only in that the opaque spots of the 

 third abdominal segment are not mentioned ; nevertheless, the synonymy 

 is not doubtful. 



Eristalis saxorum. 



JiristaUs saxorum Wiedemann, Aiiss. Zw. In8.,ii, 158; Macquart, Dipt. Exot.,ii, 



2, 33, 5. 

 Eristalis pervagus Walker (Harris), List, etc., iii, 618. 



Sa&itot— Massachusetts, Connecticut, North Carolina, Pennsylvania! 

 Georgia. 



5 , $ . Length 10 to 13™™. . Resembles dimidiatus, but is at once dis- 

 tinguishable by the third segment of the abdomen having an entire 

 posterior, velvety cross-band, by the front in the female being narrowed 

 above, and by the presence of a distinct brown spot on the wings. 



