PLECOPTEKA OF NORTH AMERICA 233 



dinal field about one-fourth the width of pronotum ; sides 

 of disc somewhat rugose. Legs brown. Wings subhyaline; 

 two or three Cu crossveins beyond M-Cu crossveins. 



Male. Seventh abdominal tergite with an elongate 

 raised, chitinous process, truncate at the tip, and reach- 

 ing well over the eighth tergite, which is membranous 

 and without any chitinous processes ; supra-anal lobe 

 small, rounded ; cerci slender, unmodified, bearing long 

 hairs ; subanal lobes quite slender ; titillators slender, con- 

 siderably shorter than the subanal lobes; ventral lobe a 

 little longer than wide. 



Female. Eighth abdominal sternite somewhat pro- 

 duced into a truncate subgenital plate, broadly emarginate 

 in the middle, the truncate lobes bearing long hairs. 



Distribution. — Two males, Ohio Pyle, Pa., Aug. 2, 1915; 

 one male, Wilmington, Essex Co., N. Y. ; two males, Sar- 

 anac Inn, N. Y., July 15, 1906; two males, three females, 

 West Falls, N. Y. 



Leuctra triloba Claassen. 



(Plate 40, figs 13, 14; plate 42, fig. 8.) 

 1923. Leuctra triloba Claassen, Can. Ent., 55:263. 



Length to tip of wings, male, 6.5 mm. ; female, 8 mm. 

 Expanse, male, 11 mm. ; female, 14 mm. 



General color dark brown. Head wider than pro- 

 thorax, brown ; hind ocelli between two and three diam- 

 eters distant from eyes. Prothorax brown, considerably 

 wider than long; front angles somewhat rounded, hind 

 angles sharp ; median longitudinal field at least one-fourth 

 the width of pronotum ; lateral discs somewhat rugose. 

 Legs brown. Wings uniformly reddish fumose. 



Male. Seventh abdominal tergite with a large, raised, 

 more or less trilobed, chitinous process which reaches well 

 onto the eighth unarmed tergite ; supra-anal lobe short, 

 rounded; cerci small, unmodified.; subanal lobes quite 

 broad and apically very finely spinulate; titillators, slen- 

 der and shorter than subanal lobes ; ninth sternite medi- 

 ally membranous and produced into a membranous lobe ; 

 ventral lobe about as broad as long. 



Female. Eighth abdominal sternite produced into a bi- 

 lobed, truncate, hairy subgenital plate which is rather 

 narrowly notched in the middle. 



Holotype, male, allotype, female, Sept. 14, 1899, Mc- 

 Lean, N. Y. (Jensen, in Cornell University Collection) ; 

 paratypes : one male, Oct., McLean, N. Y. ; one male, Sept. 



