EEY. A. E. EATON ON EECENT EPHEMEEID.E OE MATELIES. 181 



water; two-brooded. In southern Europe C. dipierum inhabiting warm sites has been 

 observed to be ovi-viviparous. 



Ti/i^e. C. d'qjterum (in Ephemera), Linn. 



Distribution. Temperate and tropical regions of the northern hemisphere ; Australia ; 

 southern Africa ; the Argentine Republic, and Chili. 



Etymology obscure. 



The nymph has been reared ; those of C. dipterum, C. rufidum, C. simile, and of one 

 of the Portuguese species have been examined by me. Through some oversight, the 

 proximal joint of the tarsus of the d intermediate leg has been omitted in PL XVII. 

 In the original camera-lucida drawing its length corresponds exactly with that of the 

 homologous joint of the hind tarsus. 



CINGALESE SPECIES. 

 CLOiiON MARGINALS, Hagen. 



Clo'e marginalis, ! Hag., Verli. zool.-bot. Gesells. Wien, viii. \:7~ (1858) & ix. 206 (1859) [excl. $ im.] ; 

 Etn., Trans. Ent. Soc. Londou (1871) 132, note. 



Subi^nago {dried). — Thorax dull luteous ; abdomen dull pitch-brown above, lighter at 

 the sides ; venter testaceous ; setae sepia-grey with black joinings. Wings transparent, 

 tinted throughout very faintly with light bistre-grey, excepting in the marginal and 

 submarginal areas, which are fuscous ; neuration light brownish. Hinder legs testaceous 

 in opaque view, changing in transmitted light to yellow-amber; fore femur luteous. 

 [Nos. 38 and 39 in Hag. Mus.] 



Imago {dried 8f fragmentary). — 6 . Thorax above fuscous or bistre-brown. Dorsum 

 of abdomen in segments 8-10 either of a similar or else of a redder brown ; segments 

 2-7 translucent whitish anteriorly, edged with bistre-brown at the tips, and extensively 

 suffused with bistre-grey before the tips, the dark colouring appearing in some examples 

 to project forwards in a pointed streak on each side from the tip of the segment ; venter 

 of a light colour, narrowly edged with a dark colour at the joinings, but apparently free 

 from other markings. Porceps similar to those of C. dipterum; a small dark acute 

 projecting point is visible above the interspace between the forceps-limbs, as in that 

 species. Fore femur, in opaque view, light brown-ochreous, with a dark band before the 

 tip ; tibia and tarsus of a rather dark amber tint. Hinder legs in opaque view of a light 

 yellowish amber tint, with dark ungues and sometimes faintly obscured tarsi, and with 

 a faintly defined dark spot, or fine abbreviated longitudinal streak, a little before the tip 

 of the femur ; knee opaque. Wing vitreous, very faintly amber-tinted in the marginal 

 and submarginal areas ; the great cross vein pitch-brown, or rufo-piceous, towards the 

 subcosta ; longitudinal neuration light brownish amber ; cross veinlets whitish. In the 

 marginal area are no cross veinlets before the bulla, but usually 2 or 8 straight ones in 

 the pterostigmatic region. 



? . Wing vitreous, coloured with light bistre-brown in the marginal and submarginal 

 areas. Neuration light brownish, excepting such of the cross veinlets as are distributed 

 in advance of the sector (4), which are whitish in most lights; those situated in the 

 coloured areas have extremely narrow translucent edging. The marginal area contains 



