PLECOPTEKA OF NORTH AMERICA 53 



Abdomen brown, paler beneath. Tails yellow, very 

 hairy on the short basal segments. 



Male. Abdominal segments normal to the 9th ; this 

 segment has a pair of minute triangular teeth beside the 

 mid-dorsal line on its apical margin ; on the ventral side 

 is a broad scoop-like semicircular projection that extends 

 its length by a third; this subgenital projection is set off 

 by a short sulcus or fold at each side. Segment ten is 

 divided as usual for the accommodation of the huge U- 

 shaped supra-anal process. A blackish six-rayed figure on 

 the dorsal side marks, the attachment of the base of this 

 process. Each side of ten is deeply cleft above into a wide 

 semicircular notch, surrounded by two slender incurving 

 strips of chitin. The upstanding tip of the supra-anal 

 process is linear blunt and cylindric and the two small 

 lateral processes at its side are thorn-like. 



Female. The subgenital plate is produced backward in 

 a long evenly rounded lobe that covers the 9th sternite 

 and overlaps upon the tenth. 



Distribution. — For type, unknown; for male neallotype 

 (described herewith), Glacier Peak and Lake Chelan Dis- 

 trict, Aug., 1921 (Ruth F. Bottomley). 



Perlodes bradleyi Smith. 



(Plate 9, figs. 4, 5; plate 10, fig. 4.) 

 1917. Protareys bradleyi Smith, Trans. Am. Ent. Soc, 43:470. 



Male. Length to tip of wings 20 mm. ; expanse 32 mm. 



Female. Length to tip of wings 23 mm. ; expanse 37 

 mm. 



Color. Brown varied with yellowish. Prothorax some- 

 what darker than the rear. The transverse M-mark in 

 front of ocelli is connected at its middle with an inverted 

 V-mark whose arms join and include the ocelli ; in front 

 of it an obscure median pale line and two lateral roundish 

 spots on the clypens. An inverted T-mark covers the rear 

 of the head, its wide stem, conspicuously yellow, is con- 

 joined basally and confluent with the very small crown 

 spot between the ocelli (no such spot present in one 

 specimen) and joined also with narrow laterally divergent 

 pale lines that mark the frontal suture, and its narrow 

 arms extended across the occipital border of the head, are 

 a little dilated the ends into obscure post-ocular pale areas. 

 These areas are more or less besprinkled with fine brown- 

 ish marmorations. Antennae yellowish brown, palpi, pale 

 yellow. 



