60 AMERICAN BLACK FLIES OR BUFFALO GNATS. 



segments gray-dusted, apical segments with numerous black hairs and 

 a few intermixed pale scales, the hairs at apex long. Legs with long, 

 yellow, scale-like pilosity on femora and upright, dorsal, black hairs 

 on these as well as tarsi, the normal paired fore tarsal hairs present 

 on apices of first and third joints; hairs on tarsi concolorous with 

 joints; claws with subbasal tooth (see PI. II, fig. 3). Wings with 

 venation normal. Halteres pale yellow, darkened at base of stalk. 



Length, 3.5-4 mm. 



Type.— Cut No. 15413, U. S. National Museum. 



Type locality, Virginia Dale, Colo., September 31, 1912 (collector 

 Bishopp). Submitted for identification by Mr. W. D. Hunter (No. 

 3065). One specimen from Glenora, British Columbia, and another 

 from Ainsworth, British Columbia, evidently belong to this or a 

 closely allied species, but their condition is too poor to say for certain. 



This species is very close to virgatum Coquillett, but the legs are 

 much darker in color ; this character is very consistent throughout the 

 series of 13 specimens), and the frons is also in most of the specimens 

 entirely glossy black. There is a slight dusting present on one or two 

 of the specimens in the series, but nothing like the thick white pol- 

 linosity which is found on that of virgatum. 



None of the specimens of virgatum bear any label as to habits, but 

 the type series of hunteri was taken on cows. The early stages are 

 ufiknown in this species. 



Simulium glaucum Coquillett. 



Male. — Black, opaque. Antennse and palpi black; face white- 

 dusted. Scutum with distinct white pollinosity, which is bright 

 silvery on two triangular patches on the anterior margin dorsad of 

 the lateral extensions of the prescutum; central opaque black stripe 

 broad and well defined anteriorly, linear and diffused posteriorly; 

 on either side of this stripe is an abbreviated linear mark which is 

 evidently the rudiment of the dorso-lateral line of virgatum., and 

 nearer the lateral margin is a broader black stripe which is dif- 

 fused on margins and anteriorly abbreviated; pleurae white-pol- 

 Jinose; scutellum slightly poUinose. Abdomen opaque black, sides of 

 segment below basal scale and apical four segments laterally silvered. 

 Legs black; femora paler at apices; tibiaj and basal joints of mid 

 and hind tarsi broadly yellow at bases; second joint of hind tarsi 

 pale at base. "Wings clear, thick veins yellowish. Halteres yellow, 

 base of stalk blackened. 



Face hairs and postocular cilia pale. Scutum with white, hair- 

 like pilosity, which is longer posteriorly and on the margins; 

 pleural tuft whitish yellow ; hairs on scutellum pale, upright. Basal 

 abdominal fringe yellow, in some lights brown; lateral hairs on 

 abdominal segments white. Legs with pale pilosity and longer, 



