72 BULLETIN 31, UNITED STATES NATIONAL MUSEUM. 



femora up to four-fifths of their length ; tibiae brownish yellow ; tarsi 

 black. In the female the femora are black at their bases only ; wings 

 hyaline, sometimes tinged with browuish ; stigma browuish, third lon- 

 gitudinal vein nearly straight. 



Three males and two females from Mount Washington. 



The facial tubercle in this species is very salient, the whole lower 

 part of the face somewhat projecting, the front of the female compara- 

 tively broad, the first joint of the hind tarsi of the male distinctly 

 swollen. The general appearance of this species is different from an 

 ordinary Syrphus." — Osteu Sacken. 



" Syrphus adolescens is represented in the British Museum by three 

 specimens; one belongs to the grou]) of S. Japponicus, the other (from 

 Nova Scotia) is *S'. americanus, the third is my /6'. contuma.r. The de- 

 scription was probably drawn from the latter, though it is very unmean- 

 ing."— O. S., Cat. Dii)t., 245. 



Syrphus mentalis, u. sp. 



Hahitat. — Washington Territory ! 



9 . Length, 9^°^. Eyes pubescent. Front shining black, extending 

 down on the sides as far as the insertion of the antennae, but the latter 

 inserted on yellow ground ; across the middle of the front with a rather 

 narrow, interrnpted, yellowish pollinose band ; pile black. Antennae 

 brownish black. Face yellow, the cheeks in front, and thence to the mid- 

 dle, along the oral margin, and a moderately broad facial stripe, reach- 

 ing acutely to the base of the autennre, black. Cheeks behind, and 

 across behind the mouth, yellow. Thorax shining greenish black, on 

 the pleurae with whitish pile. Scutellum dark, subtranslucent, only a 

 little yellowish, with black pile. Abdomen broader than the thorax, 

 shining, with three pairs of slender spots ; first pair more broadly sepa- 

 rated, their outer end attenuated, curving forward to meet the lateral 

 margin ; second and third pairs scarcely a fourth the width of the seg- 

 ments, interrupted by about their owu width, reaching nearly or quite 

 to the lateral margin; fifth and sixth segments wholly black. Legs 

 dark yellowish red; base of all the femora (on the hind ]»air including 

 the larger part), and the hind tarsi, black; the hind tibiie except the 

 base, and the front and middle tarsi, brown. Wings lightly tinged with 

 brown ; the stigma brown. 



One specimen; an additional one in the Museum of Comparative Zo- 

 ology at Cambridge. 



The front in this species is rather broad above, and the abdominal 

 spots are unusually narrow. 



Syrphus disjectus. 



Syrphus disjunctus Williston (non Macquart), Proc. Am. Phil. Soc, xx, 314 (1882). 

 Habitat. — Washington Territory ! 



S . Length, 9 to 12'""'. Eyes bare. Frontal triangle shining metallic 

 greenish black, narrowly yellow along the eyes, tlie pile, and that of the 



