KEV. A. E. EATON ON EECENT EPHEMERID/E OR MAYFLIES. 99 



above; abdominal joinings opaque. Setse rusty whitish or drab, with their bases rusty 

 Forceps-limbs light rusty-brown. Inferior spurs of the penis-lobes obliquely deflected, 

 broadly compressed and acuminate. Legs rufescent brown, changing to rufescent amber 

 in transmitted liglit ; the fore tarsus, and the tibiae and tarsi of the hinder legs, rather 

 lighter than tlie remainder. Wings vitreous, with the longitudinal neuration and the 

 opaque cross-veinlets of the pterostigmatic space of the fore wing light rufo-piceous; 

 these are somewhat irregular and variable, sometimes sparsely branched and anasto- 

 mosing, and are about 12-lG in number. 



? very similar to the d . Setaj whitish. Hind tibite and tarsi whitish, with the 

 extreme base of the tibia, the ungues, terminal joint, and the distal borders of the other 

 joints of tlie tarsus, rufescent brownisli. Wings nearly as in c? , but the nervures 

 posterior to the cubitus of the fore wing arc practically colourless ; the marginal area 

 contains about 10 weak cross veinlets between the great cross vein and the bulla, and 

 17-21 (mostly stronger) beyond that ; these are usually simple, and many of tliem 

 tapering towards the costa arc slightly curved. Length of body 8, wing, 6 8-9, 2 7-9, 

 setae, d 14 mm. 



Bab. Mount Ilood, Oregon (M'^Lach. Mus.). 



Leptophlebia rufivenosa, sp. nov. 



Siibhnago (dried), 2 ■ — Wings transparent, light yellowish brown-gi'ey ; their neuration 

 in opaque view light ferruginous brown, changing in transmitted light to rufo-piceous. 

 Setae (Vandyke) brownish grey. 



Imago (dried), ? .—Body brownish piceous, or dark rufo-piceous, with the joinings of 

 the abdominal segments of empty specimens opaque. Setse somewhat lighter than in the 

 subimago, with the joinings towards the roots, in large examples, opaqiie and narrowly 

 rufo-piceous. Fore femur in opaque view intense (ferruginous) brown-ochre, the tibia 

 and tarsus much lighter or somewhat testaceous ; the leg reflects a warm ferruginous 

 tint ; in transmitted light the femur and tibia are of a ferruginous amber-colour, the 

 trochanter and tarsus paler. Hinder legs rather lighter than the fore legs. Wings 

 transparent, the membrane lightly and uniformly tinted, and the neuration strongly 

 coloured with ferruginous ochre, the latter reflecting a reddish or golden brown and 

 transmitting a rich amber-colour. The marginal area of the fore Aving contains 7-8 

 cross veinlets before the bulla, and 17-20 beyond it ; those in the pterostigmatic region 

 are simple and slightly sinuous in small specimens, but in large examples are apt to be 

 irregular in some degree, and to anastomose in parts with one another. Length of body, 

 ? 6-8, wing 7-10, setse ira. 8-10 mm. 



Sab. Mount Hood ; Washington Territory (M'^Lach. Mus.) ; S. Raphael, Cal. (Osten- 

 Sacken, in Mus. Comp. Zool. Cambridge, Mass.), March 7th. 



(?) Leptophlebia prj^pedita, sp. nov. Plate XI. 17 c (forceps and penis, in two 

 positions). 

 Subimago (dried). — Wings sepia-grey, with pitch-brown neuration. Setse sepia-brown. 

 Imago (dried), d .—Thorax jet-black above ; alidomen pitch-brown, sometimes light 



