180 THOMAS SAY FOUNDATION 



Canada, Quebec, Saguenay River, July 25, 1906 

 (George P. Engelhart) ; Ontario Co., Hast- 

 ings (Evans). 



West Virginia, Chest River, June. 



Pennsylvania, Harrisburg, July 26; Jeannette, 

 July 28; Landisburg, June 15. 



Acroneuria arenosa Pictet. 



(Plate 4, figs. 1-5; plate 16, fig. 2; plate 28, figs. 1,2; plate 30, fig. 10.) 

 1841. Perla arenosa Pict., Hist Nat. Neur. Perlides, p. 178. 

 1907. Acroneuria arenosa Banks, Cat. Neurop., p. 11. 

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



Length to tip of wings, male, 25-27 mm. ; female, 30-37 

 mm. Expanse, male, 42-45 mm.; female, 50-62 mm. 



Color yellowish fuscous. Head wider than prothorax, 

 yellowish; area in front of ocellar triangle brownish and 

 often the ocellar triangle crossed by a brownish mark, 

 which is rounded behind and laterally extends toward the 

 base of the antennae ; sometimes the entire head pale ex- 

 cept for the darker antennal ridges and the area in front 

 of the anterior ocellus. Frontal M-ridge and lateral tu- 

 bercles fairly prominent, yellow. Ocellar triangle almost 

 equilateral; hind ocelli closer to each other than to the 

 eyes; a ring of black pigment inside the ocelli. Anten- 

 nae with basal segment infuscated, beyond yellowish. 

 Palpi yellowish brown. 



Prothorax narrower than head, wider than long ; some- 

 what narrowed behind; median line usually yellow; sides 

 disc brownish, often with yellow spots ; rugosities moder- 

 ately distinct ; angles quite sharp. Meso- and metathorax 

 yellowish brown. Legs yellowish ; femora with a wide 

 dark band just before the distal end; tarsi darker toward 

 the tip. Wings uniformly subhyaline ; veins brownish ; 

 second anal vein of hind wing with about 12 branches, the 

 branches variously anastomosing. 



Abdomen yellowish. Tails yellowish, slightly darker 

 toward the middle and beyond ; thickly covered with rath- 

 er short hair. 



Male. The ninth ventral abdominal segment with a 

 nearly rounded, or slightly transverse, distinctly raised 

 polished hammer. The genital hooks slender, cylindrical, 

 long, sharply pointed and reaching to or beyond the 

 middle of segment 10. Segments 8, 9, and 10 above 

 with short spines distributed as shown in pi. 28, fig. 1. 



Female. The subgenital plate produced over about 

 one-half of segment 9 ; the hind margin evenly rounded. 



Distribution. — Type locality, Philadelphia, Pa. 



New York, Ithaca, July 14, 1885; Ithaca, July 21; 

 Long Island, 1902. 



