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MELANDER AND BRUES. 



[VOL. I. 



base and apex, which are normal in form. The flat sides each with a wide, 

 shallow, piceous groove extending along the entire length of the tibia. 

 Tarsi black, except basal two-thirds of anterior pair. Middle tarsi with the 

 first joint longer than the two following and broadly feathered laterally. 

 Wings narrow, the anterior and posterior margins subparallel, nearly hya- 

 line. Swelling at tip of humeral vein slight, incision at tip of fifth vein 

 slight. Tegulae with long black cilia. 



Female. Length 3.5-4.5 mm. Length of wing 3.5-4 mm. Face broader, 

 gray, greenish in certain lights and darker below. Middle tibiae and tarsi 

 of the usual form. Anal lobe of wing more rounded than in the male, and 

 the costa not thickened. 



Twenty-three specimens examined. Sixteen males and six 

 females, from Rabbit Ear Pass 10,000 feet, and North Park, 

 9000 feet, Colorado. Also one male specimen from Vancouver 

 Island, collected by Mr. C. Livingston. 



This species is readily distinguished by the peculiarly formed 

 middle tibia and tarsus of the male. The female may be sep- 

 arated from latipes by its smaller size and wholly black middle 

 tarsi, and from all the other species by the entirely yellow 

 first antennal joint. 



The distribution of this species is most interesting. It is 

 one of the three species of DolicJiopus which are common to 

 Europe and North America. It is mostly a boreal species, 

 being found in great numbers throughout Northern Europe, 



from Cape North to Switzer- 

 land. In America it was 

 noticed by Loew from Alaska. 

 Where plumipes extends to- 

 ward the south it is limited to 

 high altitudes, as witnessed in 

 Switzerland and Colorado. 



Hygroceleuthus latipes Loew. 



Male. Length 5-7 mm., of wing 

 4.5-6.5 mm. Face silvery, yellowish 

 above. First joint of antennae yellow, at most slightly darkened above, 

 long. Arista pubescent. Vertex generally green. About 6 to 8 of the 

 supraocular cilia black, the remainder pale. Abdomen with posterior 

 margins of the segments cupreous. Lamellae of hypopygium white with 

 narrow black border and fringe. Anterior coxae yellow, hairy on distal 



FIG. 4. H '. latijies : a, male ; 6, female. 



