PLECOPTERA OF NORTH AMERICA 161 



Cerci lighter at base, dark towards the tip, the middle 

 segments four to five times as long as wide. 



Male. Ninth abdominal sternite produced and bearing 

 at the tip a yellow, transversely rounded knob ; tenth ab- 

 dominal tergite entire and normally retracted within seg- 

 ment nine ; subanal lobes modified into slender, finger-like 

 processes which recurve upon the tenth tergite ; supra- 

 anal lobe not modified. 



Female. Hind margin of eighth abdominal ster- 

 nite somewhat produced and deeply and squarely 

 notched in the middle. 



Genotype, Perl a ephyre Newman. 



Distribution. — East of the Mississippi River. 



Atoperla ephyre Newman. 



(Plate 15, fig. 3; plate 24, figs. 10-14.) 

 1832. Perla ephyre Newman, Mag. Nat. Hist., 3:S7. 

 1S42. Perla ephyre Pictet, Ins. Neurop., p. 283. 

 1852. Perla ephyre Walker, Cat., p. 168. 



1861. Pcrhi ephyre Hagen, Syn. Neurop. N. A., p. 28. 

 1892. Perla ephyre Banks, Cat., p. 341. 



1894. Perla ephyre Banks, Ent. News, 5:178 



1907. Perla ephyre Banks, Cat. Neurop., p. 11. 



1907. Perla ephyre Tucker, Kan. Univ. Sci. Bull., 4:78. 



1862. Perla producta Walsh, Proe. Acad. Nat. Sci. Phil., p. 365. 

 1892. Perla producta Banks, Cat., p. 342. 



1907. Perla producta Banks, Cat. Neurop., p. 12. 



1862. Perla fumipennis Walsh, Proe. Acad. Nat. Sci. Phil., p. 366. 



1892. Perla fumipennis Banks, Cat., 342. 



1907. NeoperJa fumipennis Banks, Cat. Neurop., p. 12. 



Length to tip of wings, male, 9-12 mm. ; female, 13-16 

 mm. Expanse, male, 16-20 mm. ; female, 22-28 mm. 



General color dark brown with subhyaline to fumose 

 wings. 



Head a little wider than prothorax ; with a blackish or 

 fuscous, quadrangular spot enclosing the ocelli and in 

 front extending outward to the brown lateral tubercles; 

 frontal ridge quite distinct; two ocelli which are a little 

 closer to the eyes than to each other. (In some speci- 

 mens there is a faint impression in the spot where the 

 anterior ocellus occurs when present.) Antennae brown, 

 except segments two and eight which are yellowish. 



Prothorax slightly narrower than head ; wider than 

 long; a little narrowed behind; brown to blackish, some- 

 times variegated with yellow and brown; front angles 

 narrowly, hind angles more broadly rounded ; surface 

 somewhat rugose. Legs brown; femora somewhat dark- 

 er above ; tarsi darker, first and second tarsal segments 

 short, subequal, third tarsal segment at least twice as 



