PLECOPTERA OF NORTH AMERICA 275 



widened behind ; angles narrowly rounded ; surface slight- 

 ly rugose. Legs brown. Wings of male abbreviated, 

 reaching only about half the length of abdomen in some 

 males, while in others they reach nearly to the tip of the 

 abdomen; wings of female reach almost to tip of abdo- 

 men; venation very irregular; anal field of hind wings 

 nearly as long as wing. Abdomen brown (last two or 

 three segments blackish in male)j cerci composed of 

 about 15 segments. 



Male. Just before the raised hind margin of eighth 

 abdominal tergite occurs a black, blunt rounded tubercle, 

 finely granulate above and directed cephalad; supra-anal 

 process recurved, short and divided into two parts, the 

 upper flat, heavily chitinized, bluntly rounded at tip and 

 above, closely beset with short hairs, the lower process 

 in the form of a hollowed out sheath with an enlarged 

 bulbous tip and without any notches on the margin ; ninth 

 tergite with a depressed membranous area, tenth tergite 

 bifid; ninth sternite slightly produced and evenly 

 rounded ; subanal lobes triangular, ending in short spine- 

 like processes. 



Female. Eighth abdominal sternite unmodified. 



Distribution. — Holotype, male, allotype, female, March 

 16, Ithaca, N. Y. (Cornell University Collection) ; many 

 species, mostly males, Ithaca, March ; two males, Inter- 

 laken, N. Y., Nov. 21, 1912; one male, two females, Feb. 

 16, 1907, Dedham, Mass. (G. M. Allen) . 



Capnella incisura Claassen. 



(Plate 50, figs. 10, 11.) 

 1924. Capnella incisura Claassen, Can. Ent., 56:45. 



Length to tip of wings, male, 3 mm. ; female, 5-5.5 mm. 

 Expanse, male, 4 mm. ; female, 8-8.5 mm. Length to tip 

 of abdomen, male, 3.4 mm. ; female, 5 mm. 



General color dark brown to blackish. Head wider than 

 prothorax ; dark brown ; occiput with longitudinal darker 

 lines ; hind ocelli at least three times as close to eyes as to 

 each other. Antennae with about 22-25 segments. Pro- 

 thorax quadrangular, slightly widened behind ; angles 

 rounded ; surface nearly smooth. Legs brown. Wings of 

 male reaching over one-half to two-thirds of abdomen, of 

 female as long or slightly longer than abdomen ; anal field 

 of hind wings nearly as long as rest of wing. Abdomen of 

 female above with a broad median light longitudinal band 

 which extends to the hind margin of the eighth tergite ; 

 tergites nine and ten evenly chitinized ; male abdomen 



