LiLLiE. — On New Zealand Ephemeridae. 167 



middle or a little way before the middle, and tapers gradually 

 to its oblique apex. Cross-veinlets abundant in the fore wing. 

 At the terminal inargin the longitudinal nervures are provided 

 with curved simple branchlets, and there are no isolated 

 veinlets. The two intercalar nervures of the anal-axillar 

 interspace of the fore wing have simple branchlets, and 

 usually the hinder one close to its proximal extremity curves 

 forwfcird to unite with the other, which similarly curves for- 

 ward to unite with the anal nervure. Guard at the orifice 

 of the mesothoracic spiracle small and triangular. Forceps 

 limb of male 3-jointed, the proximal joint much longer than 

 the remainder, somewhat compressed, and in its basal half 

 broadly dilated beneath ; the deflexible basis, usually pro- 

 minent in the middle of the distal border, is otherwise merely 

 eniarginate ; the corresponding lobe in the female, usually 

 bifid and sharply excised with acute triangular points, is 

 seldom emarginate only. Segments 6-10 constitute about 

 half of the abdomen ; segment 8 (the longest) is nearly 

 equalled by segment 7 ; the others are successively shorter. 

 Median caudal seta about as long as the others, seldom 

 thrown off by specimens ; outer setae, in both sexes, usually 

 double the length of the body. Tarsal ungues all nearly 

 alike, small, narrow, and hooked at the tip. In normal 

 species the male fore tarsus is nearly as long as the tibia, or 

 a little longer than it, and the latter is about one and a half 

 times as long as the femur ; the female fore tarsus is nearly 

 half the length of the tibia, which is about one and one- 

 third times as long as the femur. 



Nymph. Hitherto unknown. Considering the marked 

 differences in the two nymphs here described, it is hard to 

 say what the generic characters might be. 



Atalophlebia scita, Walker. 

 Nymph ? (living). Plate XIV., figs. la-p. 



General colour brownish-black or greyish- black ; e-yes 

 black ; wing-covers black or lighter grey ; double median 

 line along dorsal surface of the abdomen ; terminal segment 

 yellow ; tracheal branchiae yellowish-grey, veins pitch-black ; 

 legs dusky grey, a yellovv^ spot at the proximal and distal 

 ends of the femora ; setae dull grey, becoming lighter towards 

 the extremities ; middle seta slightly longer ; angle between 

 the setae about 50°. Length of body, 9 mm. ; length of setae, 

 12 mm. 



The colour differs according to the interval from moulting. 

 Young nymphs and individuals just moulted are greenish- 

 grey. The moults are many. The males in the later stages 

 are distinguished by their bi-lobed eyes, the upper lobes being 

 red. 



