THE CANADIAN ENTOMOLOGIST 211 
prcescutum light fawn-brown with a very dark brown median 
stripe and much paler lateral vittae; the conspicuous median stripe 
is broadest in front, gradually narrowed behind, ending before the 
transversie suture and narrowly bisected behind; lateral prsescutal 
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 3'ellow, the knol3s 
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; R2+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. CMonea primitiva, sp. n.; cf, legs of the right side not 
figured; w = wing. 
Fig. 2. C. gracilis, sp. n.; cf , dorsal aspect, legs of the left side 
not figured. 
Fig. 3. Antenna of Pterochionea hradleyi Alexander; d^. 
" 4. The same, Chionea primitiva; cf . 
" 5. Wing of Erioptera noctivagans, sp. n.; cf . 
"6. " E. cinereipleura, sp. n.; cf . 
" 7. " Limnophila cressoni, sp. n.; 9. 
" 8. " L. subaptera, sp. n.; cf . 
" 9. " L. aspidoptera Coquillett; cf . 
" 10. " Tricyphona aperta Coquillett; cf • 
" 11. " T. dege?terata, sp. n.;cf . 
"12. " Rhaphidolabis sessilis, sp. n.; 9. 
" 13. " R. major, sp. n.; 9. 
