PLECOPTERA OF NORTH AMERICA 189 



Distribution. — Type locality, Three Rivers, Cal. 



Wyoming, Yellowstone River, Aug. 5, 1921 (F. 



M. Sallee). 

 Montana, no locality. 

 Canada, Maligne Lake, Alberta, July 1-3, 1915 



(E. L. Diven). 

 California, Three Rivers. 

 Texas, no locality. 



Acroneuria lycorias Newman. 



(Plate 28, figs. 11, 12; plate 30, fig. 7, and text fig. S.) 

 1839. Perla lycorias Newm. Am. Mag. Nat, Hist., 3:85. 

 1883. Perla navalis Prov. Pet. Faun. Can. Neurop., p. 73. 

 1908. Acroneuria excavata Banks, Trans. Am. Ent. Soc, 34:256. 

 1922. Acroneuria lycorias Needham and Claassen, Can. Ent., 54:252. 



Length to tip of wings, male, 20-28 mm. ; female, 30-35 

 mm. Expanse of wings, male, 32-46 mm. ; female, 42-55 

 mm. 



Color yellowish with darker markings. Head wider than 

 prothorax, a dark brown spot covers the ocellar triangle. 

 It is rounded in the rear and laterally extends to the base 

 of the antennae. Tubercles yellowish brown, remainder 

 of head yellow except beyond the eyes externally. Ocelli 

 form an equilateral triangle, the rear ones are closer to 

 each other than to the eyes and are rather conspicuously 

 ringed with black pigment. Antennae brown, yellowish 

 for a little way beyond the first segment. Palpi brown. 



Prothorax narrower than the head, a fourth wider than 

 long, yellowish with bosses that are usually brownish, a 

 little darker about the borders. Meso- and metathorax 

 yellowish brown, darker in the middle. Legs yellow. Fe- 

 mora with a dark transverse band across the distal end 

 and a more or less triangular spot at the base above. 

 Wings uniformly subhyaline. Veins brown. Veins beyond 

 the cord few or wanting. 



Abdomen yellow, a little infuscated on the side. Tails 

 yellow at base, darker beyond, covered with short hair. 



Male. The ventral prolongation of the 9th segment 

 bears the usual polished disc or hammer, oval in form and 

 smooth. Genital hooks are flattened, triangular, sharply 

 pointed at their anteriorly directed tips. Segments 9 and 

 10 both are well covered with minute prickles. 



Female. The subgenital plate is slightly produced to 

 rearward, the hind margin varies between being evenly 

 rounded or truncate or slightly excavated in the middle. 



