190 EEV. A. E. EATON ON EECENT EPHEMERID^ OE MATELIES. 



AMERICAN SPECIES. 



Cloeon mendax, Walsli. 



VMmendax, Walsh, Proc. Acad. Nat. Sc. Pliilad. (1862) 381. 

 Cloeon mendax, Etu., Trans. Ent. Soc. London (1871) 106. 



Subimago, 6 . — Wings and their neuration subopaque and slightly dusky. Setae pale. 

 Turbinate eyes pale ; lower segment of oculi blackish (Walsh). 



Imago, 6 . — Pale ferruginous ; sternum and venter pale greenish hyaline, the latter 

 opaque at the tip. Legs pale, tips of tarsi cloudy. Wings and neuration hyaline ; isolated 

 veinlets of the tei'minal margin all single. The 2 sometimes has the thorax tinged with 

 green, and is always paler above. (After Walsh.) 



? {dried). — Body light yellowish ochraceous above, sometimes very light, and com- 

 monly liable to infiltration of chlorophyll, especially at the roots of the setae, the peak 

 of the mesonotum, the wing-roots, the knees, and the tarsi. Venter whitish ochraceous ; 

 the main tracheae of the abdomen often blackened. Setae white. The marginal area of 

 the wing has no cross veinlets between the great cross vein and the bulla ; in the ptero- 

 stigmatic space are 4-8 cross veinlets (usually 6) from the costa, mostly simple, rather 

 oblique, and almost straight, very rarely anastomosing with one anotlier to any extent, 

 many of which do not reach the subcosta ; and usually, between them, a few rudiments 

 of others issue from the costa. Length of body 4-6, wing 5-6 mm. 



Bab. Rock Island, 111. (Walsh) ; Denham, Mass. (M^Lach. Mus.) ; Detroit, Mich. 

 (Mus. Comp. Zool., Cambridge, Mass.). May and June. 



Cloeon vicintjm, Hagen. 



Cloericina, Hag., Sraithson. Miscell. Coll. (1861) Synop. Neuropt. N. Am. 5i; id., Proc. Ent. Soc. 

 Philad. ii. 178 (1863). 



Cloeon vicinuni, Etn., Trans. Ent. Soc. London (1871) 107. 



Imago {dried). — d . Thorax fulvous (Hag. 1861) or reddish brown {id. 1863) ; abdomen 

 whitish hyaline, with the last 3 segments fuscous above ; setae whitish. Wings colomdess. 

 Legs whitish, the fore legs fulvous at the base. 



? . Body yellowish white ; setae and legs whitish ; wings hyaline. Length of body 4 ; 

 expanse of wings 10 ; setae, 6 10, $ 6 mm. (After Hagen.) 



Hab. Washington (Osten-Sacken). 



? Cloeon dubium, Walsh. 



Cloe dubia, Walsli, Proc. Acad. Nat. Sc. Philad. (1862) 380; Hag., Proc. Eut. Soc. Philad. ii. 178 

 (186.3). 



Cloeon dubium, Etn., Trans. Ent. Soc. London (1871) 100. 



Mr. Walsh diagnosed this species from BaHtis lyropinquus (which it closely resembles) 

 by its smaller dimensions &c. 



Imago. — 6 . Thorax and last 4 dorsal segments piceous : these last, beneath, opaque 

 whitish ; the intermediate abdominal joints transparent whitish, each with a dark dot 

 on each side, whose centre is hyaline. Legs pale, the tips of the tarsi cloudy. Wings 



