1891.] A. E. Eaton — Notes on some native Ephemerid^. 411 



together witli the extremity of the area nest behind it, and narrow- 

 cloudy bordering along the aabcosta in front and the radias behind (the 

 former more extensive in the beginning of the pterostigtnatic space) as 

 well as along the cross veinlets; in addition to spots : in this sex the 

 spots are larger than in the 2 (but not much larger) and therefore are 

 hardly so small as in B. supposita ; the best marked are three in the 

 usual positions in the midst of the wing, viz: — one at the prasbrachial 

 fork and the others on the cubitus and the first sector, but occasionally 

 cross veinlets or the ends of nervures are clouded in the usual places of 

 other spots found in species of Ephemera, such as at the inner ends of 

 the shortest of the sectorial intercalar nervures, or at the junction of the 

 pobrachial with the 2nd or 3rd cross veinlet beyond the fork of the prse- 

 brachial nervure, or near the base of the wing between the pobrochial 

 and anal nervures either on the nearest cross-veinlet or at the extremity 

 of the foremost intercalar nervure. The terminal margin of the hind 

 wing is narrowly bordered with a light, raw umber grey cloud aud 

 several of the cross veinlets are pitch black. 



The abdominal markings resemble those of E. supposita in most 

 respects : those of the 1st segment are not well shewn in the specimens 

 at hand : the 2nd segment in place of dorsal streaks has on each side 

 an irregular transverse quadrangular blotch, narrowed upwards and 

 obliquely truncate above ; the 3rd to the oth segments have two sti^eaks 

 and the 6th to the 8th segments three dorsal streaks on each side, all 

 longitudinal and sub-parallel, the lowest of which is linear and narrow, 

 the next to it double the width and usually more curved, and the inner- 

 most (where there are three) narrow and tapering at both ends. In the 

 9th segment a broad stripe takes the place of the lowest and the inter- 

 mediate streak combined. On the pleura, in nearly every segment, is a 

 short black dash at the base ; but the 10th segment has a black blotch. 

 Setae light raw umber brown; the joinings mostly (excepting in the 

 basal half of the median seta) narrowly dark brown. Fore femur in 

 opaque view either raw umber brown or rufo-piceous : tibi^ dark pitch 

 brown ; tarsus lighter ; trochanter and coxa subochreous. Hinder legs 

 in opaque view, translucent yellow ochre, with the obtuse claw pitch 

 brown. In transmitted light, the fore femur and tarsus become ferru- 

 gineous amber, and the hinder legs yellow amber. 



2 Very similar to the (J. Thorax brown ochreous, with a black 

 spot in front of each tegula, a black longitudinal stripe on each side of 

 the pronotum, and a black irregular line down the outer side of the fore 

 coxa. Fore femur brown ochreous ; fore tibse bistre brown or light pitch 

 brown ; fore tarsus paler. Wings nearly colourless, with indistinct 

 and minute spots, placed singly at the bulla of the sub-costa, behind 



53 



