126 



MELANDER AND BRUES. 



[Vol. I. 



5. Front femora with the basal two-thirds infuscated ainnicola sp. nov. 

 Front femora wholly yellow Aldricliii Wheeler 



6. Arista with slight pubescence ; wings usually with a stump-vein at the 



bend of the fourth vein ........ 7 



Arista bare ........... 8 



7. Second joint of hind tarsi yellow at base ; legs yellow ; smaller species 



crenatus O. S. 

 Second joint of hind tarsi black ; legs darker ; larger species 



coHsangiiineus Wheeler 



8. Tegular cilia wholly black, somewhat robust . . ciliatus Aldrich 

 Tegular cilia yellow at sides ....... 9 



9. Wings yellowish anteriorly, coxae yellow . . . ajflictus O. S. 

 Wings hyaline, coxae darker .... idahoensis Aldrich 



Hygroceleiithus Wheelerii, sp. nov. 



Male. Length 5 mm. ; length of wing 4 mm. Shining metallic cupre- 

 ous green. Proboscis piceous. Face covered witli a thick dust, silvery 

 on lower half, becoming golden towards antennae. Antennae yellow, first 

 two joints wholly so, the third black on upper surface and outer half. 

 First joint hairy above, and with a shght swelling on inner surface to meet 

 the other antenna ; second joint tipped with a fringe of black hairs, becom- 

 ing stouter and longer on underside, 

 nearly one-half the length of first joint 

 when viewed from above. Third 

 joint somewhat longer than the first, 

 bearing dorsally a stout arista with 

 very short pubescence. Vertex me- 

 tallic violet. Postocular cilia deli- 

 cate, black above and light yellow 

 below. Thorax bright grassy green, 

 becoming cupreous at sides and with 

 a faint indication of the two narrow 

 approximated median brown lines. 

 Abdomen green, with silvery dust at sides and beneath. Posterior margins 

 of segments becoming cupreous and margined with piceous. Hypopygium 

 green, almost piceous, overlaid with a grayish dust. Lamellae pale, with a dis- 

 tinct narrow dark border and a black fringe. Internal appendages yellow. 

 Sides of thorax glaucous ; shining green when viewed from behind. Fore 

 coxae yellow, hairy on whole anterior face and with a few bristles at tip. 

 Middle and hind coxae yellow with outer face glaucous at basal two-thirds. 

 Trochanters, femora, and tibiae yellow. Middle tibiae very long and thin, 

 the proportion of femur to tibia of the middle leg being 20 to 39. Hind 

 tibiae not incrassate, nor with smooth space on inner surface. Anterior 

 tarsi black from tip of first joint, middle and hind tarsi black. Middle 



Fig. 2. — H. Wheelerii: a, wing of male ; 

 b, middle leg; c, antenna. 



