198 TUE CANADIAN ENTOMOLtKJIST. 



4. Two black spots or a band on face under the antennae ; femora 



banded in the middle 5. 



No black spots on face under antennte 7, 



5. No dash in wing ; about two cross-veins margined with black near the 



place, thorax brownish H. frontalis. 



A dark dash in wing, thorax and abdomen often yellowish 6. 



6. A spot each side on face under antenna? ; abdomen mostly 



pale //. interpunctiita. 



A band on face under antennae ; abdomen usually 



darker //. Canadensis. 



7. All costals before bulla broadly margined with black, also some other 



cross-veins ; small species //. maculipennis. 



Not so many costals margined 8. 



8. Small species, veins hyaline // simplex. 



Larger species, veins yellowish, costal area yellowish. H. JJavescens. 

 Veins brown or marked 9. 



9. Femora unbanded in middle, veins all brownish ....// placita. 



Femora banded in middle 10. 



10 Two small dark dots on median carina between antennas, thorax 



dark //. tripunctata. 



No such dots '. I r. 



1 1 . Thorax and abdomen very pale ; the longitudinal veins mostly 



pale // pulchella. 



Thorax and abdomen darker, some of the longitudinal veins brown . 1 2. 



1 2. Apical costal area darker; larger species, 10 mm. long . H. luridipennis. 

 Apical costal area not much darker ; smaller species, 8 mm. 



long H. terminata. 



Heptagenia marginalis, n. sp. 



A rather large pale species, but not as pale as //. Jfavescens, the 

 anterior margin of the produced clypeus black : pronotum each side with 

 a black stripe, and the lower margin black ; a black mark on the hind edge 

 of coxa I, one each side of coxa II, one behind the last and rather above 

 it, and one above coxa III at base of abdomen, dorsal segment narrowly 

 margined behind with black, and a dark oblique stripe each side, setae 

 rather dark ; venter pale, unmarked, exce|)t the ventral plate of female is 

 rather darker ; this plate is nearly hemispherical and nearly covering the 

 next segment ; wings faintly darker along the costal area, especially near 



