EEV. A. E. EATON ON RECENT EPHEMEEID.E OR MAYFLIES. l73 



translucent and concolorous, but sometimes subopaque ; the subcosta and radius of the 

 fore wing', the base of the costa, and tlie wing-roots, subopaque and pallid, or pale 

 yellowisli brown. Legs in 2 lutescent, rather more dingy in eolour in the d . Seta3 pale 

 warm sepia-brown, Avitli opaque joinings. Tliorax in s luteous or lutescent, varied with 

 paler ; abdomen above luteous or brown-ochre, darker or more of a reddish brown at the 

 sides of the segments and in the midst of their hinder extremities ; venter ochraceous 

 yellow. 



Imago [dried).- — d . Wings vitreous, with light brown neuration ; 3-6, subregular, 

 mostly simple, oblique cross veinlets in the pterostigmatic space of the fore wings, some- 

 what attenuated or tabescent towards the subcosta ; between them, almost midway 

 between this last and the costa, is extended a single series of granulated rudimental 

 longitudinal veinlets, rarely branched, but somewhat irregular. Hind wing binerved. 

 Thorax yellowish testaceous, varied near the peak of the mesonotum with llavescent. 

 Dorsum of abdomen partially brown-ochre, with dark spots at the stigmata ; segments 

 2-5 or 6 translucent at the sides and towards the base, their extreme liinder borders 

 piceous ; segments 9 and 10 pale. Venter and forceps pale yellowisli ochraceous ; the 

 8th segment and the forceps towards their extremities dark ; seta? whitish, tinged with 

 pale sepia-grey, and having several of their basal joinings dark reddish brown. Femoi"a 

 amber-colour, gradually darkened and more distinctly tinged towards their tips with 

 reddish testaceous ; tibiae and tarsi testaceous, the ungues, and the extreme terminal 

 margins of the intermediate joints of the hinder tarsi, rubiginose. Length of body 4 ; 

 wing 4!"5-5mm. 



Hab. Eainbodde, Ceylon, at altitudes of 4000 feet and upwards (Nos. 23, 27-30, and 

 perhaps 52 in Hag. Mus.). The specimen numbered 52 has tlie neuration and terminal 

 margin of the fore wings piceous ; and the neuration is stronger than that of any of the 

 other examples. 



A Nymph allied to Centroptilum, generis iiicerti. 



Nameless Nymph. Plate XLV. (whole figure and details). 



Abdominal tracheal branchiaj all somewhat alike in form, ovate-lanceolate and acute, 

 traversed lengthwise by an irregularly piunately branciied trachea. Autennne defective in 

 the type specimens, shorter than the head and thorax combined. Median caudal seta 

 subequal to the others in length, which are about h as long as the body ; the fringes are 

 narrowed acuminately to the points of tlie seta?. Mandibles nearly as in Ba'etis. Palpus 

 of maxilla i. longer than the laciuia; the terminal joint minute, the others long and 

 slender, the first about | as long as the second ; the laciuia armed at the point with about 

 two teeth, preceded on the inner edge by fasciculated setuhe of nearly uniform length. 

 Labium and maxilla? ii. nearly as in Baietis; but the palpi are not indented at the joining 

 of the oval-pointed terminal joint Avith the penultimate joint, which is well defined; the 

 proximal joint of the same is subequal in length to the other two combined. Tongue 

 truncate at the base, broadly emarginate in front ; the median lol)e dilated distally and 

 mucronate ; the much narrower paraglossa? slightly expanded, with curved lateral borders 



