PLECOPTERA OF NORTH AMERICA 265 



the hind ocelli towards the base of antennae. Head cov- 

 ered with yellowish hairs which are quite long on the 

 clypeus and labrum ; surface not rugose. Ocelli from an 

 almost equilateral triangle whose base is a little longer 

 than the sides; hind ocelli at least twice as close to eyes 

 as to each other. Antennae dark brown or blackish. Palpi 

 blackish brown. 



Prothorax black, narrower than head, wider than long ; 

 sides convex, front margin slightly, but evenly rounded; 

 front angles broadly rounded ; hind angles more narrowly 

 rounded; surface rugose but the rugosities not very 

 strong; covered with fine yellowish pile. Meso- and meta- 

 thorax black. Legs brown ; in some specimens very dark, 

 in others lighter brown with the femora darker towards 

 the distal end. Wings uniformly hyaline or very slightly 

 fuscous ; veins brown ; Sc reaches almost to the cord ; R 

 sinuate at origin of Rs. 



Abdomen dark brown, hairy. Cerci or tails yellowish 

 brown (lighter in the specimens with light brown legs 

 and darker in those with dark legs) ; slightly darker 

 towards the tip; hairy, shorter hairs all over segments 

 and long hairs on the apical part of the individual seg- 

 ments. 



Male. Seventh tergite prolonged backward into a 

 raised rather broad truncate process or tubercle. Supra- 

 anal process recurved and reaching to the process on seg- 

 ment seven; bifid, narrower at the base and much wider 

 in the middle. At the tip it sends a ventral process or 

 tongue under the tubercle on segment seven. 



Female. The eighth abdominal sternite is not pro- 

 duced ; the middle portion of the segment smooth and 

 somewhat swollen. 



Cotypes, male and female, No. 11366, in Banks Collec- 

 tion, Museum Comparative Zoology, Cambridge, Mass. ; 

 three females from Colorado, 1853 ; one female from 

 Steamboat Springs, Colo., May 27. 



Capnia columbiana Claassen. 



(Plate 49, figs. 6, 7.) 

 1924. Capnia columbiana Claassen, Can. Ent., 56:47. 



Length to tip of wings, male, 7 mm. ; female, 10 mm. 

 Expanse, male, 12 mm. ; female, 17 mm. 



General color blackish brown. Head wider than pro- 

 thorax, blackish ; lateral tubercles large, flat, polished ; 

 ocelli small, hind ocelli almost three times as close to eyes 

 as to each other; antennae blackish. Prothorax about 



