PLECOPTERA OF NORTH AMERICA 121 



small transverse tubercle; subanal lobes small, unmodi- 

 fied. 



Female. Hind margin of eighth abdominal sternite 

 produced into a broadly rounded subgenital plate which 

 normally extends about half way across the ninth ster- 

 nite. 



Holotype male, allotype female, June 11, 1923, San An- 

 tonio Canyon, near Claremont, Calif. (Theresa Robinson, 

 in Cornell University Coll.). 



Paratypes, three males, three females, from same lo- 

 cality. 



Alloperla signata Banks. 



(Plate 20, figs. 5, 6.) 

 1895. Chloroperla signata Banks, Trans. Am. Ent. Soc, 22:314. 

 1907. Alloperla signata Banks, Cat. Neur., p. 13. 



Length to tip of wings, male, 7-8 mm. ; expanse, male, 

 12-14 mm.; length to tip of wings, female, 8.5-11 mm.; 

 expanse, female, 15-18 mm. 



General color yellow with two blackish spots on the 

 head and a broad blackish stripe on the prothorax. 



Head slightly wider than prothorax ; a black, somewhat 

 triangular spot covering the ocellar triangle and a smaller 

 triangular black spot in front of the ocellar triangle with 

 its apex reaching almost to the front ocellus ; remainder 

 of head pale yellow; hind ocelli a little closer to the eyes 

 than to each other ; antennae yellowish at base, brown be- 

 yond; palpi brown, the- apical segment very small, es- 

 pecially in the maxillary palpi. 



Prothorax wider than long ; disc transversely oval ; yel- 

 low, usually with a broad median anchor-shaped blackish 

 stripe, widened at both ends but more so in front than 

 behind; sides of disc somewhat rugulose; legs yellowish, 

 tarsi brownish, wings hyaline with a greenish yellow 

 tinge ; subcosta very faint, reaching to a point half way 

 between the origin of the radial sector and the cord. 



Abdomen brownish with a broad median interrupted 

 dark stripe. Cerci yellow, darker toward the tip, especial- 

 ly the tips of the individual segments. 



Male. Supra-anal lobe consists of a very short, brown, 

 upturned, bluntly pointed process, minutely granulate; 

 subanal lobes very small, triangular; ninth abdominal 

 sternite prolonged beyond the tip of the abdomen ; tenth 

 abdominal segment partly cleft above and almost wholly 

 withdrawn into segment nine ; penis beset with stout 

 hairs at the tip. 



Female. Hind margin of eighth abdominal sternite 



