PLECOPTERA OF NORTH AMERICA 103 



Male. Abdominal segments normal to the fifth, the 

 fifth tergite much produced rearward into a bilobed proc- 

 ess, with a deep narrow notch between the lobes, the 

 lobes closely beset with short prickles; tergites 6 to 9 

 largely membranous ; 6 and 7 smooth, 8 with many 

 prickles and behind with a small median lobe; the 9th 

 tergite usually also has a few prickles; the 10th tergite 

 bears a pair of genital hooks as shown in Plate 19, figures 

 8 and 10; abdominal sternites 3, 4 and 5 armed with stiff 

 hairs and 6, 7 and 8 with hairs and prickles ; ninth ster- 

 nite slightly produced and rounded behind ; subanal lobes 

 triangular, unmodified. The metasternum bears a patch 

 of stiff hairs. 



Female. The hind margin of the eighth abdominal 

 sternite slightly produced into a subgenital plate, which is 

 medially notched as shown in Plate 19, fig. 7. 



Distribution. — 



New York, Ithaca, March 25 - Sept. 24; Ithaca, 

 Coy Glen, July 22 ; Keen Valley, Aug. 9, 1889 ; 

 Wilmington, Essex Co., Aug. 11, 1888; Lud- 

 lowville, Mt. Whiteface, Aug. 22-24, 1916; 

 Hamilton Co. ; Ogdensburg, July 18, 1906 ; En- 

 field, July 25, 1920. 



Pennsylvania, Ohio Pyle, Aug. 8, 1905. 



New Hampshire, Jackson, Sept. 22 (Owen Bryant). 



.Maine, Eagle Lake, Sept. 8, 1907 (J. A. Cush- 

 man). 



Georgia, Tallulah Falls, June 19-26, 1909 (J. 

 C. Bradley). 



North Carolina, Black Mts., June, 1912 Beuten- 

 miiller) . 



Quebec, Chatianguay. 



Perla media Walker. 



(Plate 13, fig. 3; plate 19, figs. 4, 5, 6.) 



1852. Perla media Walker, B. M. Cat. Neurop., p. 145. 



:S61. Perla media Hagen, Syn. Neurop. N. A., p. 24. 



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



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



1923. Phasganophora media Klap. Coll. Selys, IV, 2:95. 



1861. Perla lurida Hagen, Syn. Neurop. N. A., p. 21. 



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



Length to tip of wings, male, 20-22 mm. ; female, 26-32 

 mm. Expanse, male, 35-38 mm. ; female, 45-54 mm. 



General color dark brown to blackish, varied with yel- 

 low. 



