EEV. A. E. EATON ON EECENT EPHEMERID.E OE MAYFLIES. 231 



AMETROFUS, Albania, 1878. 



Illitstrations. AduU (details), PL XXII. 38. 



Adult. — Pore tarsus of 6 nearly 5 (about 4f) times as long as the tibia, wliicli is f as 

 long as the femur ; the tarsal joints in diminishing sequence rank, 1, 3, 2 equal to 4, 5 

 [the intermediate joints probably vary slightly iu their mutual proportions], the first joint 

 about 1^ as long as the second and almost twice as long as the tibia. Pore leg of 2 

 about y as long as the body ; tarsus about 2f as long as the tibia, and this f as long as 

 the femur ; the joints in the order of their shortening rank 1, 2, 3 equal to 4, 5, and the 

 first joint is about IJ as long as the second, and little shorter than the tibia. Ungues 

 mutually dissimilar in every tarsus. In the anal-axillar interspace of the fore wing 

 figured the two intercalary nervui-es next to the anal nervure are the longest. Hind 

 wings well developed ; the dilatation of the marginal area angular in front ; the axillar 

 region ample and supplied with abundant neuration, to which tlie hindermost nervvire 

 contributes numerous branchlets. Porceps basis of 6 deeply and roundly excised, with 

 acute points ; forceps-limbs 4-jointed ; the proximal joint stout, nearly § as long as tlie 

 second, which is the longest; the other joints short. Ventral segment 9 of $ formerly 

 (as was that of Siphlurus, erroneously) described as lobeless ; but it is just possible that 

 (as in the genus alluded to) a very short obtuse lobe may have been overlooked. Median 

 caudal seta about as long as the others ; those in ? imago about If as long as the body ; 

 in ? subimago about as long as the body. 6 Oculi evenly contoured. 



Ti/])e. A.fragiiis, Albarda. 



DistribntioH. Holland. 



Etymology . ai.ieTpoc. and ttovc, from the excessive length of the d fore tarsus compared 

 with the tibia. 



The proportion of the total length of the 6 fore leg to the body is perhaps only as 

 11 to 14 approximately ; but this estimate rests upon the assumption that the original 

 drawings of the 6 and $ legs were uniform in scale of enlargement, which, though very 

 probable, is not absolutely certain. 



AMETROPrs FRAGiLis, Albarda. Plate XXII. 38 (wings, legs, and genitalia). 

 Ametropus [type] fragiUs, ! Albarda, Ent. Mo. Mag. xv. 129 (1878) ; ! Etii. op. cit. xviii. 22 (1881). 



Sttbimago (dried). — Wings uniformly light smoky grey, with light yellowish or 

 testaceous longitudinal nervures. Setse testaceous. 



Imago {dried), 6 . — Notum pitch-brown. Abdomen bistre-brown above, testaceous 

 at the joinings and towards the sides ; venter in segments 2-7 yellowish, in 8 and 9 

 fuscescent ; forceps testaceous ; sette whitish. Pore leg testaceous, with the tibia, and 

 the femur distally, dull piceous. Hinder legs somewhat of a light brownish ochre. 

 Wings vitreous ; longitudinal neuration light amber-colour ; cross veinlets colourless, 

 those in the pterostigmatic portion of the marginal area of the fore wing numerous, 

 mostly simple, and gently curved. 



2 . Very similar. I'ore leg rufo-piceous, with the base of the femur, the joinings, and 

 the terminal joint of the tarsus testaceous. Setie very light warm-sepia or cologne-earth 



31* 



