PLECOPTERA OF NORTH AMERICA 149 



veins. Abdomen dark brown ; tails brown, the individual 

 segments darker at the tip. 



Male. Ninth abdominal sternite much produced and 

 somewhat truncate behind ; eighth sternite with a knob 

 which is about as wide as long and is closely beset with 

 very short prickles ; subanal lobes modified into very long 

 slender hooks which recurve upon the tenth tergite; su- 

 pra-anal process not developed. 



Female. Subgenital plate of eighth abdominal sternite 

 produced over about a third of the following segment 

 and with a broad, shallow median emargination. 



Holotype, male, allotype, female, April 26, Lakehurst, 

 New Jersey (Cornell University Collection). 



Paratypes, three females, same locality as types. 



Isoperla signata Banks. 



(Plate 27, figs. 4, 5, 6.) 

 1902. Perlinella signata Banks, Can. Ent., 34:124. 

 1907. Isoperla signata Banks, Cat. Neurop., p. 13. 



Length to tip of wings, male, 13-14 mm. ; female, 14-16 

 mm. Expanse, male, 23-25 mm. ; female, 25-28 mm. 



General color dark brown with yellow spots on head, a 

 yellow median prothoracic stripe and greenish infuscated 

 wings. 



Head a little wider than prothorax ; dark brown with a 

 yellow spot in the ocellar triangle, a yellow spot in front 

 of the anterior ocellus, yellow at base of antennae and 

 with the occiput yellow (there is considerable variation in 

 the color pattern on the head, but the yellow ocellar spot 

 is usually present) ; hind ocelli much closer to the eyes 

 than to each other; antennae brown. 



Prothorax much wider than long ; sides straight ; some- 

 times slightly narrower behind ; angles slightly rounded ; 

 a wide median yellow band which is widened behind ; disc 

 brown, somewhat rugose ; sometimes a little yellow on the 

 lateral margins. Legs brown, tarsi darker. Wings lightly 

 greenish f umose ; veins heavy brown ; subcosta ends be- 

 fore the cord ; a series of costal crossveins before the end 

 of subcosta and one (rarely two) beyond ; usually no cu- 

 bital crossveins in hind wing. 



Abdomen and tails brown. 



Male. Hind margin of ninth abdominal sternite much 

 produced and rounded behind ; hind margin of eighth 

 sternite with a rounded knob which is about as wide as 

 long; subanal lobes recurved upon the tenth tergite and 

 bluntly pointed. 



