REV. A. E. EATON ON IIECENT EPHEMEEID.E OR MAYFLIES. 267 



Heptagenia interpunctata, Say. 



\Baetis inter punctata, Say, Journ. Acad. Nat. Sc. Pbilad. viii. 11 (1839) ; Pict., Hist. Nat. Nevropt. 

 ii., Epliem. 19J, (18i3-5) ; Walk., List of Neuropt. in Brit. ^Mus. part iii. 5(52 (1853); Le Coute, Com- 

 plete Writiug.s of T. Say, ii. 411 (1859); Hag., Smitlison. Miseell. Coll. (18G1) Syuop. Neuropt. N. 

 Am. 44. 



\Palingenia interpundata, Walsh, Proc. Acad. Nat. Sc. Pliilad. (18G2) 374; Hag., Proc. Ent. Soc. 

 Philad. ii. 177 (1863) ; Walsh, op. cit. ii. 190 (18G3). 



Heptagenia inter punctata, Etn., Trans. Ent. Soc. London (1871) 112. 



Suhimago. — Wiugs at first opaque aud tinged -with yellowish, afterwards becoming 

 fuscous; neuratiou fuscous, excepting the basal f of the costa, subcosta, and radius, 

 which are yellowish, aud the neuration of the axillar region of the fore wing, which 

 (like the whole neuration of the hind wing, except at the tip) is light amber-coloured. 



Imago, 6 . — Yellowish. Eyes during life pale greenish yellow, bisected horizontally 

 by a black line ; near their uj^per orbits is a black spot on eacli side, sometimes obscured 

 by the vertex being obfuscated, aud again below each of tlie antennoo is anotlier black 

 spot a little elongated transversely, which appears angular only when viewed obliquely. 

 Prothorax marked with a black triangle at the base and a black line on each side ; notum 

 piceous. Abdomen in segments 2-7 or -8 " pale obscure greenish hyaline " [?=traus- 

 parent and tinged faintly with greenish], with the terminal ^ of each of them, and a 

 median longitudinal Hue or stripe on the dorsum piceous, which stripe is usually broad, 

 and when broad contains a pale spot on each side : the remaining dorsal segments almost 

 entirely piceous: venter ]}a\e, obscure greenish, with the tips of the segments darker; 

 forceps pale, sometimes cloudy at the tips. Setre pale greenish, narrowly fuscous at the 

 joinings, except in one immature specimen. F5re leg pale greenish yellow, with a 

 median and a terminal band on the femur, the tip of the tibia, aud tlie joinings and tip 

 of the tarsus fuscous. Hinder legs somewhat paler, but similarly marked on the femur 

 and at the extremity of the tibia, excepting in one instance where the median femoral 

 bands were wanting. Wings hyaline ; the fore wing clouded with yellowish brown 

 along the costa, especially in the pterostigmatic space, and the hind wing tipped 

 distinctly with brown ; behind the bulla, in the midst of the inters])ace between the 

 radius (3) and the sector (4) of the fore wing is a very coarse black longitudinal streak 

 about O'o mm. long : neuration for the most part fuscous ; but in their basal two thirds 

 the costa, subcosta, and radius are yellowish ; the cross veinlets in the marginal and 

 submarginal areas of the fore wing are very coarse. 



2 . Differs from the d in having the black triangle at the base of the prothorax 

 reduced to a dot ; meso- and metanotum luteous. Al}domen in segments 2-9 egg-yellow 

 above and beneath, with the piceous markings much narrower than those of the d , and 

 with the ventral joinings pale instead of dark ; segment 10 whitish. In the fore wing 

 the costal border is uniformly clouded with yellowish, not darker in the pterostigmatic 

 space, and the neuration in proximity to the inner margin, like that of all but the tip of 

 the hind wing, is yellowish hyaline. Length of body G-10 ; Aving, d 8-11-5, ? 8-14 ; 

 setae, d im. 20-25, subim. 9-15, 2 im. 14-24, subim. 7-14 mm, 



Bab. Eock Island, 111. [after Walsh]. Also Indiana (Say) ; Alleghany Mts., Va., 



Washington, D.C., Trenton Falls and Chicago (Osten Sacken, teste Ilag.). 



30* 



