84 EEV. A. E. EATON ON EECENT EPHEMElilD.E OR MAYFLIES. 



6-10 constitute about J 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 (in some 

 species treble) the length of the body. Tarsal ungues all nearly alike, small, narrow, 

 and hooked at the tip. In normal species the d fore tarsus is nearly as long as the 

 tibia, or a little longer than it, and the latter is about 1^ as long as the femur ; the ? 

 fore tarsus is nearly ^ the length of the tibia, and this about IJ as long as the femur ; 

 in both sexes the tarsal joints, arranged in diminishing succession, rank thus: — 3, 2, 4, 5, 1. 

 Hind tarsus visually about ^ the length of the tibia. Some Cingalese species have the 

 d fore tarsus rather shorter than the tibia, and the joints in diminisliing order rank 2, 3, 

 4, 5, and 1, while tlie hind tarsus is scarcely ^ as long as the tibia. 

 Nymph unknown. 



Type. A. australls (in Ephemera), Walker. 



Distribution. S. Africa, Ceylon, Australasia, Japan (undescribed sp.), and S. America. 

 Etymology. uTa\6g and <fiAtj3ioi', in allusion to the delicacy of the cross veinlets of the 

 wings of some species. 



In the absence of female examples of most of the species, I am unable to separate 

 satisfactorily those referred to above, as deviating from the typical form, from the others 

 which exhibit the normal characteristics of the genus. Judging from analogy, there is 

 much probability that the differences in the proportions of the setpe to the body, and in 

 the proportional lengths of the joints of the limbs, distinguishable in the adult flies, are 

 attended with manifest differences in the nymphs. The nymphs should be searched for 

 under stones in shallow water at the borders of streams, or in proximity to the outflow 

 of pools in river-beds, where the current is gentle, favourable sites would be indicated 

 by females alighting upon the water to oviposit, and by the departure from it of sub- 

 imagines. 



Atalophlebia pasciata, Hag. Plate LXIV. 1 (penis). 



Potamanthus fasciatus,\ Hag., Verb, zool.-bot. Gesells. "Wien, viii. 476 (1858) [part]. 



Imago [dried), d . — Thorax testaceous, with a brown-ochreous longitudinal stripe in 

 the midst of the mesonotum followed by some dark blackish clouds near the peak. 

 Abdomen very pale ochreous, approaching dull straw-colour; segments 2-8 and 10, 

 narrowly edged at the tips with pitch-black, segments 7 and 8 ochreous-brown above, 

 the two foUowiug yellow ochreous ; venter subochraceous, slightly darkened at the 

 joinings of the segments. Setae clove-brown, their joinings near their insertions dark ; 

 forceps lutescent. Wings vitreous ; fore wings faintly tinted with yellowish in the 

 marginal and submarginal areas, and provided with about 20 simple slightly curved 

 cross veinlets in the pterostigmatic space ; longitudinal neuration yellowish, cross veinlets 

 black, many of those in the anterior portion of the fore wing and some near the wing- 

 roots edged narrowly with black. Legs fusco-lutescent, the femora banded in the middle, 

 broadly but not strongly, with darker. Length of body 11, Aviug 15, setaB 35 mm. 



Hub. Rainbodde, Ceylon, at an altitude of over 4000 ft. The subimago formerly 

 attributed to this species is a female Ephemera mpposita. The coloration of the body 



