282 REV. A. E. EATON ON RECENT EPHEMERID.E OR MAYFLIES. 



wiug throughout, excepting only the neuration. Ventral lobe of segment 9 ellipsoidally 

 rounded off. Length of body 10-11 ; wing, j 12-14, $ 14 mm. ; seta) defective. 



Hab. Greece (Stein, in Berlin Mus.) ; Albania (Sir S. Saunders), 2 cJ , 1 ? im. (in 

 M'^Lach. Mus.). 



Part V. Road November ISth, 1886. 



I FIND myself unable to decide, from dried specimens, whether E. lielveticus, venosus, 

 and forcipula are entitled to rank as species only or as races. It is possible, if speci- 

 mens were grouped in accordance with their style of coloration, that JE. forcipula might 

 justly be held to bear the same kind of relationship towards H. lielveticus, as the var. 

 qucpsitor to E. venosus, and that the peculiar shortness of the first joint of the d fore 

 tarsus of E. helceticiis may be found to be something less than a specific distinction. 

 On the 3rd of June, 1885, I captured two 6 imagines of E. venosus by the river at Eden 

 Lacy in Cumberland, having the tai'sal joint in question percejjtibly shorter pro- 

 portionally than that joint is in any other specimens caught elsewhere, or at other times 

 in the same place, during that year. Specimens of E. venosus that have been relaxed 

 and set out for the cabinet after they have become dry in the first instance are very apt 

 to lose their markings and to be rendered unserviceable for study ; and I liave conse- 

 quently found it difficult to institute comparisons between the unset specimens in my 

 own collection, and a large proportion of those from other collections submitted to me 

 for identification. 



EcDYUBTJS HELVETicus, sp. nov. Plate XXIV. 46 a ( d fore tarsus). 



XBaJdtis Xvenosus, Pict., Hist. Nat. Nevropt. ii. Epliem. 1G7, pi. .\x. [part.] (1813-5). 



Subimago {living). — Wing-membrane either fumatose or dusky, tinged at the base of 

 the fore costa and again beyond the middle with bright or sulphur-yellow, but elsewhere 

 in the basal half of the same with dull greenish, approaching olive-green ; fore wing 

 marked with the usual dark stripes ; terminal margin of the hind wing broadly bordered 

 with dark grey. Eyes of 6 dull yellowish green, traversed l>y a reddish-brown line, and 

 displaying a movable black spot ; those of 2 dark and dull olivaceous. Eore femur of 

 6 pitch-brown ; tibia rather lighter ; hinder femora dull greenish grey or olivaceous ; 

 tarsi black ; setae pitch-black ; forceps black. 



Imago [dried), 6 . — Notum light brownish or pitch-brown. Eore leg of d uniformly 

 piceous, with the first tarsal joint short for an Ecdyurus. Pterostigmatic S2)ace of the 

 fore wing darkened. Abdomen nearly ixniformly brownish above, with the following 

 exceptions : — in transmitted light on each side of the base in segments 2-7 a smal 

 colourless translucent narrow space or spot, rounded below, extends nearly to the anterioi 

 dorsal trachea of the segment ; and between the two dorsal tracheae of the segment, the 

 shallow, oval depression (covered in the nymph by the tracheal branchia) is rather palei 

 than its borders. — {Living). Eyes sometimes intense- bistre or pitch-brown above, some 

 times rich rufo-fuscous, and traversed below by a dark or rusty line edged with ligh 



