THE CANADIAN ENTOMOLOGIST 211 



praescutum light fawn-brown with a very dark brown median 

 stripe and much paler lateral vittse; the conspicuous median stripe 

 is broadest in front, gradually narrowed behind, ending before the 

 transversie suture and narrowly bisected behind; lateral praescutal 

 stripes and the lobes of the scutum paler brown; remainder of 

 the scutum, the scutellum and postnotum reddish yellow, the 

 latter browner on the caudal half. Pleura pale reddish brown, 

 very sparsely dusted with whitish. Halteres yellow, the knobs 

 brown. Legs with the coxae dull yellow; trochanters similar, 

 their margins blackened; femora dull yellow, the tips narrowly 

 brown; tarsi dark brown. Wings yellowish gray subhyaline, 

 strongly iridescent; stigma very pale; veins dark brown. Venation 

 (fig. 13) Rs long, almost straight; cross-vein r removed from the 

 tip of vein Ri to a distance about equal to its own length; Ri+z 

 shorter than the radial cross-vein. 



Abdomen grayish brown with a reddish cast that is best 

 defined on the caudal margins of the terminal sternites; ovipositor 

 reddish yellow. 



Holotype, 9 , Horseman Creek, Geneva Park, Grant, Colorado, 

 altitude 10,200 feet, July 19, 191G, (L. O. Jackson). 



This is the largest species of the genus. 



Explanation of Plate XII. 



Fig. 1. Chionea primitiva, sp. n.; cf, legs of the right side not 



figured; u' = wing. 



Fig. 2. C. gracilis, sp. n.; d^, dorsal aspect, legs of the left side 



not figured. 



Fig. 3. Antenna of Pterochionea hradleyi Alexander; cf . 



" 4. The same, Chionea primitiva; cf . 



" 5. Wing oi Erioptera noctivagans, sp. n.; cf . 



" 6. " E. cinereipleura, sp. n.; cf . 



"7. " LimnopJiila cressoni, sp. n.; 9 . 



" 8. " L. siibaptera, sp. n.; cf . 



" 9. " L. aspidoptera Coquillett; cf. 



"10. " Tricyphona aperta Coquillett; cf . 



" 11. " T. degenerata, sp. n.;d'. 



" 12. " Rhaphidolabis sessilis, sp. n.; 9. 



" 13. " R. major, sp. n.; 9. 



