112 REV. A. E. EATON ON EECENT EPHEMEEID^ OE MAYFLIES. 



Distribution. South Africa. 



Etymology. qSjjv and ^\e^iov, from the abundance of cross veinlets in the wings. 



Adenophlebia dislocans, "Walker. Plate XIII. 21 (wings, legs, forceps, and penis). 



XEphemera dislocans, ! Walk., Trans. Ent. Soc. Loudon, N.S. v. 198 (1860). 



Leptophlebia dislocans [$im.], and auriculata \_^\m.'], ■ Etn., op. cit. (1871), 83, pi. iv. 24-246 

 [details] . 

 Adenophlebia dislocans, ! Etn., Ent. Mo. Mag. xvii. 194 (1881). 



Imago (dried). — 6 . Thorax above black. Abdomen light pitch-brown, the dorsal 

 joinings opaque, the darker colour produced obliquely downwards and forwards at the 

 sides of the segments. Setae in some lights pitch-black, changing to intense sepia-brown 

 in others. Fore legs in opaque view either pitch-brown or rufo-piceous, in oblique view 

 either very intense opaque raw-umber brown, or reddish brown, and in transmitted light 

 either translucent dark brownish amber or rufescent amber ; hinder legs rufo-piceous in 

 ojoaque view ; femora each with a dark submedian band, and with the extreme tip dark. 

 Wings vitreous, the hind wings posterior to the subcosta (2) tinged with piceous-grey ; 

 nearation piceous, becoming blacker or browner when the posture is varied ; cross 

 veinlets strongly defined in the marginal and submarginal areas of the fore wing ; in the 

 former area are about 6 cross veinlets before and 10 beyond the bulla ; those in the 

 pterostigmatic region are simple and slightly curved. 



? . Thorax piceous above. Abdomen discoloured ; the apical borders of the inter- 

 mediate dorsal segments piceous or blackish, the dark colouring produced forwards into 

 a pair of oblique triangular streaks on both sides of the back of each (viz. a streak at the 

 postero-lateral angle, and another between that and the median line), so arranged that 

 each streak of the inner series is continuous with a streak of the outer series in the 

 antecedent segment. Setae piceous at the base and intense sepia or warm sepia-brown 

 towards their extremities. Pemora luteo-piceous, banded nearly in the middle with black, 

 and pitch-brown at the extremity ; tibiae and tarsi rufo-piceous. Wings vitreous, their 

 neuration in opaque view piceous, in transmitted light browner ; cross veinlets of the fore 

 wing (excei)ting those adjacent to the terminal margin, and those in the extremity of the 

 pterostigmatic space) bordered with Vandyke-brown or dark warm sepia-brown, which 

 gives rise to small irregular spots in the midst of the wing between the base and the 

 middle, and to rounded spots just behind the radius (3) and in some other situations ; at the 

 base of the costa a spot of a like colour occupies the space between the wing-roots and 

 the cross veinlet nearest to the great cross veui : in the marginal area are about 7 cross 

 veinlets before the bulla, and 15, mostly simple oblique and straight, beyond it. The 

 cross veinlets of the hind wings are narrowly bordered, and the membrane distally is 

 tinged with light reddish brown-grey. Length of body, s 9; wing, d 9, ? 6 ; setae, 

 d 20, $ 18 mm. 



Scib. Cape Colony, Graham's Town. As the hind wings of the ? (in Brit. Mus.) are 

 exactly like those of the d (in M°Lach. Mus.), I referred both to a single species in 1881. 

 Sexual differences in the marking (and even the neuration) of the wings, are met with 

 in some other Ephemeridce, notably iu Cloeon dipterum and (coloration only) in 

 Hagenulus. 



