Diptera 67 c 



Type locality: West of Bernard harbour, Dolphin and Union straits, 

 Northwest Territories, July 14, 1916 (F. Johansen). 



The type specimen differs frona any previously described species of the 

 genus in having four postsutural dorso-centrals. If the specimen is abnormal 

 m this respect it can be separated from nitens by the presence of the long bri- lies 

 on the antero-ventral surface of the mid femora; from the species identified by 

 btem as alpicola Rondani, by the yellowish wings, almost bare arista, and I he 

 mid-femoral bristles. 



A third species which occurs in the United States, and which resembles 

 alpicola, is separable from quadrisetosa by the more loosely pilose fore tarsi, the 

 more widely spaced and longer bristles on latero-ventral margins of the mid 

 and hind tarsi, the darker wings, and-the shorter papU, the latter being less than 

 half as long as the apical portion of the proboscis. 



A fifth, and probably a sixth species, found in Colorado, are very distinct 

 from quadrisetosa. 



Pogonomyioides, n. gen. 



Generic Characters. 



Female. — Resembles Pogonomyia, differing principally > i the prealar 

 bristle being weak or absent and in having the pteropleura with a number of 

 long hairs on centre. The only species of Pogonomyia in which I have seen 

 any hairs on the pteropleura is the one described in this paper. In addition to 

 the above characters the intra-alar bristles are practicallj^ absent in Pogonomy- 

 ioides, usually only the posterior one being distinguishable and that very 

 weak, and there is no long bristle at apex of fore tibia on venter, nor are there 

 any conspicuous bristles at apices of fore tarsal joints ventrally. 



In other respects as Pogonomyia. 



Type, Pogonomyioides atrata, n. sp. 



Pogonomyioides atrata, n. sp. 



Female. — Puparium: Brownish red, slightly shining. Surface microscopic- 

 ally granulose, almost without strise above, finely but very distinctly transversely 

 striate ventrally, becoming more coarsely so posteriorly. Posterior portion of 

 cephalopharyngeal skeleton very slender, as shown in PI. IX, fig. 30; dorsal 

 half of thoracic segments absent; apex with a concentrically ridged rim sur- 

 rounding a small but deep cavity; locomotor processes apparently lacking, 

 except in center of each ventral segment, where there is a single transverse 

 series of microscopic elevations extending nearly across the segments; a single 

 series of small, stitch-like impressions between all segments, which is duplicated 

 -and surrounds the lateral fusiform area, three or four, short, irregular, longitudinal 

 series of minute elevations on each segment laterally; base of abdomen with 

 the pair of respiratory tubercles well developed, slender, about six times as 

 long as thick at base; apical segment irregularly shrunken (possibly abnormal), 

 a large depression caudad of spiracles and extending forward to posterior margin 

 of penultimate segment, a subtriangular depression situated in extreme apex, 

 and a large one on lateral area; spiracles slightly elevated, separated by less 

 than three times their own diameter, the openings directed dorsad, ventrad, 

 and laterad respectively. 



Length, 6-5 mm. 



Imago: Black, slightly shining.' Orbits and upper part of cheeks silvery 

 pilose. Thorax with slight greyish pruinescence, distinctly but not conspicu- 

 ously quadrivittate. Abdomen slightly and evenly grey pruinose. Wings clear. 

 Calyptrse yellowish. Halteres black. 



Frons about two-fifths the width of head, each orbit above about one-fifth 

 as wide as interfrontalia; interfrontal cruciate bristles strong; orbitals as in 



Vol. iii— 46963— 5J 



