THE CANAiDIAN ENTOMOLOGIST 135 



that enclose it widely divergent. 



Abdomen dark brown, paler laterally. Male hypopygium with the distal 

 lateral angles of the pleurite provided with numerous blackened spines; prox- 

 imal face of pleurites with long, erect bristles; two pleural appendages, these 

 short and stout, approximately equal in size, the outermost clavate, the head 

 with numerous black spicules; inner appendage pale, the apex broadly and 

 obtusely rounded. Lateral gonapophyses long and slender, approximately as 

 long as the pleurites themselves. 

 Habitat. — Idaho. 



Holotype, c^, Moscow Mt.. July 25, 1920 (R. C. Shannon). 

 Allotopotype, $. 



Rhaphidolabis subsessilis is closely related to R. nibesccns Alex. (North- 

 eastern North America) but is readily told by the presence of but twelve an- 

 tennal segments, the coloration and the elongate lateral gonapophyses of the 

 male hypopygium. In its general appearance it is more like R. major Alex. 

 (Colorado), a very different fly. 



Kliaphilolabis (Plectromyia) rediieta, new species. 

 General coloration (in alcohol) pale brownish yellow, the praescutum in- 

 distinctly darker medially ; antennae with only eleven segments ; wings hyaline, 

 the stigma lacking; cell Ra petiolate; abdomen with a subterminal darker brown 

 ring. 



Male.- — Length 4.2 mm. ; wing 5 mm. 

 Described from alcoholic material. 



Rostrum obscure yellow ; palpi short, brown. Antennae brown, the basal 

 segment paler ; f lagellum with only nine segments ; flagellar segments long-oval, 

 gradually decreasing in size to the end. Head yellowish brown. 



Meisonotum pale brownish yellow, the praescutum indistinctly darke|r 

 medially ; scutal lobes slightly darkened. Pleura yellow. Halteres pale, the 

 knoljs l)r()\vn. Legs witli the coxae and trochanters light yellow; remainder of 

 the legs pale brown, the tibiae a little darkened at the tips. Wings hyaline ; 

 stis^ma lacking; veins brown. Venation: R^ comparatively short, strongly 

 arcuated; petiole of cell R3 long, subequal to the basal deflection of Rv •; 

 outer deflection of R^ perpendicular or nearly so, close to the tip of Rt ; cell 

 Ml lacking, as in the subgenus, petiole of cell M^ longer than this cell; basal 

 deflection of Cui a short distance beyond the fork of M. very faint, without 

 macrotrichiae. 



Abdominal tergites light brown ; sternites more yellowish ; segments seven 

 and eight dark brown. Male hypopygium with the pleural appendages short, 

 stout, the tips blunt ; one appendage is more slender, near the tip provides with 

 several spinous setae, the other appendage very short and stout with the distal 

 and blunt, set with several short spines and about two long, delicate bristles. 



Habitat.- — Idaho. 



HolotyPc (^. Moscow Mt., July 25, 1920 (R. C. Shannon). 



Paratopotypc, ^. 



This small fly presents an a])i)earance that is very similar to the type 

 of the subgenus Plectromyia except that the cell R3 is petiolate. The reduction 

 in number of antennal segment is very interesting and difficult of explanation. 

 Within the group Dicranotae there is now found a range of from eleven to 



