BUFFALO SOCIETY OF NATURAL SCIENCES 185 



villi of the fore tarsi a little enlarged ; fore and middle tarsi a 

 little longer than their tibiae, the first joint about as long as the 

 three following ; hind tarsi shorter than their tibiae, the first joint 

 longer than the second. Tegulae, their cilia and the halters pale 

 yellowish white. Wings hyaline ; veins brownish, yellow at 

 the root of the wing; first vein reaching two-fifths of the dis- 

 tance to the tip of the second. 



Described from one male from Hood River, Ore. ; and one 

 male from Lewiston, Idaho. Type in the collection of Prof. 

 J. M:. Aldrich. 



The specimen from Idaho has the tips of the hind tibiae and 

 the hind tarsi brown, and the hair on the venter somewhat shorter. 



27 Diaphorus aldrichi, n. sp. 



Male : Length -2.7,5-3 mm. Face broad, a little longer than 

 wide, when viewed from in front black, from the side or above 

 silvery white ; palpi small, black with stiff black hairs ; antennae 

 black, third joint rather large, subquadrate, scarcely as long as 

 broad ( Fig. 5 ) ; arista dorsal ; front and occiput blue-green, the 

 pollen of the face extending somewhat above the antennae ; cilia 

 of the inferior orbits white. Thorax and abdomen bright blue- 

 green, the former with thin whitish pollen around the edges 

 of the dorsum; pleurae more thickly white pollenose; abdomen 

 with rather long white hair on the lower lateral sides and on the 

 venter ; hypopygium concealed ; bristles at tip rather long. Coxae 

 and femora blue-green ; femora with a row of stiff hairs on the 

 lower front edge ; fore coxae with long white hairs on the front 

 surface; extreme tips of fore and middle femora and their tibiae 

 yellow ; hind tibiae and all the tarsi blackish ; middle tibiae with 

 a bristle on the front side near the knee ; hind tibiae with a row 

 of bristles above. Tegulae, their cilia and the halters yellow. 

 Wings hyaline ; second section of the costa one and a half times 

 as long as the first ; costa scarcely thickened beyond the tip of 

 the first vein; third vein distinctly arched so as to run closer 

 to the second vein than in most species ; the fourth vein also 

 bent beyond the cross vein but nearly parallel with the third 

 towards the tip. 



Described from two males taken at Boise, Idaho. Type 

 in the collection of J. M. Aldrich. 



