ART. 23 TWO-WINGED DOLICHOPODID FLIES VAN DUZEE 19 



robusta these bristles are as long as the diameter of the joint and 

 very conspicuous, while in olhiventHs there are only very small 

 bristles, if indeed they could be called bristles, they are but little 

 longer than the hairs on other portions of the joint. A. roMsta is a 

 much larger species and the female is much stouter than that of 

 albiventris. 



Kedescribed from many males and females taken at Hull, Quebec, 

 where the type specimen was taken. Have seen specimens taken by 

 Doctor Aldrich at Craigs Mountain, Idaho, May 24, 1902. One 

 male taken at Algonquin, Illinois, June 6, 1895. Two males taken in 

 South Dakota; one male taken at Bozeman, Montana, June 20, 

 1911; and one male taken at Portage, New York, July 1, 1917. 



13. ARGYEA CILIATA Van Buzee 



Argyra ciliata Van Duzee, Proc. TJ. S. Nat. Mus., vol. 63, art. 21, p. 5, 1923. 



This was described from one pair taken by Doctor Aldrich at Fair- 

 banks, Alaska. 



Ti/jje.— Male, Cat. No. 25958, U.S.N.M. 



14. ARGYRA BIMACULATA, new species 



Male. — Length, 4.7-5 mm. Face rather wide, silvery white. Front 

 thickly covered with white pollen. Antennae black; first joint with 

 numerous stiff hairs above; third joint nearly three times as long 

 as broad ; arista apical, about as long as third joint. The small black 

 orbital cilia do not reach down to the middle of the eye. Beard 

 yellowish, not abundant. 



Dorsum of the thorax green with rather thick yellowish-wliite 

 pollen; pleurae black with white pollen; scutellum with four large 

 marginal bristles, and with a few conspicuous black hairs on its 

 disk. Abdomen gi-een with its hair and bristles black; second seg- 

 ment with a rather large, third with a small yellowish spot on each 

 side; still, these spots are not conspicuous; abdomen with a nar- 

 row line of white pollen at the base of each segment, and some yel- 

 lowish-brown pollen visible in certain lights on the dorsum. Hy- 

 popygium (fig. 14) black; outer lamellae small, black, somewhat 

 triangular; inner appendages testaceous, large, shining, nearly bare, 

 still having several small hairs. 



Coxae black, fore and middle ones with numerous black, bristly 

 hairs. All femora black, fore and middle ones narrowly yellow 

 at tip; anterior pair with long black hair on posterior surface, 

 which is about as long as the thiclaiess of the femora; middle pair 

 with a row of black bristly hairs on lower anterior edge, which 

 are not as long as the width of the femora. All tibiae yellow, 

 posterior pair black at tip, this black shading into the yellow. Fore 



