PLECOPTERA OF NORTH AMERICA ;)7 



Female. Length of body 15 mm.; of antennae 11 mm.; 

 of tail 10mm. 



A long horned, long tailed, long legged, short winged 

 species of dirty olivaceous-fuscous color obscurely varied 

 with pale, the middorsal stripe and the crown spot on the 

 head being the more conspicuous marks. The color pat- 

 tern is best developed in the female specimen and is as 

 follows : head brownish, paler on the labrum, on the mar- 

 gins of the clypeus, on the crown spot between the ocelli, 

 on the extreme occiput, and on two large post-ocular spots 

 extending from the eyes to the hind angles of the head ; 

 the latter are brown at the sides. The M-mark across 

 the frons is not very plain and is somewhat abnormal, 

 the portion adjacent to the middle ocellus being swollen 

 and enlarged, and the ends of the M relatively small. 

 Antennae fuscous, paler at base of flagellum. 



Prothorax, squarish with a wide collar at the front, 

 straight parallel sides, and a deep middle sulcus in the 

 midst of a broad pale middorsal stripe that widens 

 strongly at its ends. Embossed markings on sides of disc 

 few, coarse, and irregular. Middle stripe continued on 

 mesothorax but obscure there. Wings dull smoky brown, 

 with a darker wash across the base in a faint streak at 

 front and rear. Wing tips reach the level of the tip of 

 the abdomen in the female and are a very little shorter 

 in the male. Veins brown. Legs olivaceous, with rather 

 plain washes of brown in. rings on femora and tibiae adja- 

 cent to the pale knees. Tails, olivaceous at base, becom- 

 ing darker at tip. Abdomen black, paler at tip on seg- 

 ments 9 and 10. 



Male. Similar to P. signata but with a narrower trans- 

 verse cleft in the dorsal edges of the split tenth segment, 

 and the genital hook at its rear is pointed, and not broadly 

 rounded on its tip. 



Female. Subgenital plate a broad bifid scoop extend- 

 ing across the 9th sternite, inflated in the middle, its thin 

 cleft tip with approximated obtuse points appressed 

 against the 9T;h sternite. Pale, except for two basal 

 brown marks at the side, which are repeated on the sides 

 of the 9th and 10th sternites. 



This species is similar to P. signata but smaller and more 

 plainly colored, and its rear ocelli are farther apart, being 

 closer to the eyes than to each other. 



Distribution. — A single pair, male holotype, female allo- 

 type, from Mt. Lyell, Calif., taken at an altitude of 11,000 



