EEV. A. E. EATON ON RECENT EPIIEMERID.E OR MAYFLIES. 145 



&c. 583 (1853).— C. grisea, Pict., Hist. &c. 278, pi. xlv. 1, 2 {18i3-5) ; Walk., List &c. 581 (1853) ; 

 Brau., Neuropt. Austr. 25 (1857) ; Aiisscr., Ann. A. Soc. Nat. Modena, Ann. iv. 133 (18G9) ; ! Joly, 

 Bull. Soc. Hist. Nat. Toulouse, iv. 147 (1871) ; id., Bull. Soc. d'Et. &c. Augers, 41-2, Note B (1876).— 

 C. halterata, ! Hag., Eut. Ann. (18(33), 11. 



Subimago [Umng). — Wiugs tinted with greyisli, especially towards the costa. Setae 

 light blackish grey. 



Imago {Uc'ing). — d . Head gi'ey-black, with the stipes of the antennae and the cervical 

 joining sepia-grey. Pronotum medium ivoiy-black ; meso- and metanotum jet-black, 

 changing to pitcli-ln-own when dried. Alidomen of 6 grey, tinged towards the sides 

 with medium ivory-black ; each dorsal intermediate segment has the track of the dorsal 

 vessel, and a spot on each side of it at the base of the segment, pellucid, and each of 

 those segments beneath has a pellucid spot on each side near the middle; the dorsal 

 joinings of the segments are opaque, with the extreme overlapping edge of the integu- 

 ment whitish. Setce grey, with light blackish-grey joinings. Legs pitch-black ; the 

 tibiae, tarsi, and under edges of the femora light blackish-grey and translucent. Wings 

 transparent, smoky, slightly greyish in the vicinage of the costa for some distance from 

 the wing-roots ; costa, subcosta and radius, and in some lights the other longitudinal 

 nervures pitch-black ; but viewed with transmitted light, in some positions, most of the 

 nervures mentioned, excepting the thicker parts of the three foremost, become trans- 

 lucent whitish. 



2 [living). — Fore femur grey ; hinder femora yellowish white. Abdomen above 

 l)lackish grey, becoming ochreoiis towards the joinings and sides of the segments ; venter 

 tinged with greenish grey. Length of body, 6 4-5, ? 6 ; wing, d 4-5, $ 7 ; setae, 

 6 im. 14 & 15-15 & 16, subim. 3; ? im. & subim. 2-3 millim. 



Hub. Europe, from Scania and Smalaud (Wallengren) or Lapland (Zet.) to Portugal 

 and Italy ; and from Great Britain to Germany and Switzerland. Abundant at Cintra, 

 27th April (400-COO ft.) ; Toulouse (430 ft.) ; Bale and Geneva ; and near San Marcello, 

 in the Apennino-Pistojese (2200 ft.). The form of the spot on the forceps-basis varies 

 considerably in dried examples, and sometimes the spot disappears in drying. 



CtENis kobusta, sp. nov. 



Imago {dried), d .—Thorax lucent raw-umber or light pitch-brown, the pronotum 

 rather paler laterally, the vertex of the head rather redder brown, approaching light 

 burnt-umber. Abdomen greyish white above; the joinings very narrowly grey-black, 

 liordered narrowly with whitish at the bases of the segments ; the dorsal vessel and the 

 sides of tlie dorsal segments pale, the lighter space encroaching largely upon the darker 

 in segment 7 ; genitalia stained slightly with brown-ochreous ; venter and forccps-ljasis 

 uniformly whitish ; setae white. Legs whitish ; fore femur and base of fore tibia varied 

 with sepia-grey ; ungues and hinder femora whitish yellow-amber. Wings transparent, 

 slightly smoky along the costal margin ; costa, subcosta, and radius for some distance 

 from the wing-roots dark sepia-grey. 



2 . Head and thorax rather similar in colour to those of the 6 . Abdomen opaque 

 with light greyish dorsal markings (dark grey in the subimago) upon a dull light brown- 



