EEV. A. E. EATON ON EECENT EPHEMERID.E OR MAYFLIES. 205 



Chirotonetes ignotus, Walker. Plate XIX. 33 b (wings, J , head, and forceps). 



%Ba.etis iynota^ ! Walk., List of Neuropt. Ins. iu Brit. Mus. part iii. 571 (1853). 



II Isonychia iynota, ! Etu., Traus. Eut. Soc. London (1871), 135, pi. vi. 29. — /. ferruyinea, ! Albarda, 

 Ent. Mo. Mag. xv. 128 (1878) ; ! Etn., op. cit. xvi. 36 (1879). 



ISipMurus, sp. , ! Rostock, Jahresb. d. Ver. f. Natm-k. Zirickau, 1877, p. 88 (1878). 



Sub'miago {living), 6 . — Eyes subolivaceous. Wings somewhat fawn-colour, becoming 

 {ivhen dried) dull light brownish ochre or yellowish brown, bordered narrowly along the 

 terminal margin with ivory-black grey, and marked in the anterior wing with two or 

 three evanescent dusky nebulae or abbreviated transverse streaks from the fore margin, 

 due to the grouping of the cross veinlets, which are very narrowly edged with black (or 

 when dried with light grey) ; neuration yellowish (like the membrane), with the 

 exception of a few cross veinlets in the marginal and submarginal areas between the 

 great cross vein and the bulla, which are black. 



Imago (living), 6 . — Eyes light red or brownish red, with the orbits ochreous, and 

 with a movable black round spot or curved streak. Xotum pitch-brown or (when dried) 

 rufo-piceous. Abdomen purple-brown above (when dried dull \'enetian-red brown), with 

 the joinings of the segments very narrowly brownish, the terminal segments rather paler 

 than the others, and the edges of the pleuraj ochraceous ; venter spotless, unless (as in 

 dried examples) marked in segments 2-8 with a median light brownish Venetiau-red 

 triangular spot pointing forwards and extending from the hinder margin to the base of 

 the segment, leaving on each side a pale triangular space of the lighter ground-colour. 

 Setse whitish, but piceous near their insertions, with this darker colour gradually shaded 

 off. Eorceps dusky, paler at their joinings. Fore leg piceous ; the tibia and tarsus 

 pitch-black, excepting the bases of the tarsal joints and the ungues, which are pale. 

 Hinder legs lutescent straw- colour, or [when dried) bright amber-yellow, with the ter- 

 minal tarsal joint and the outer claw dusky. Wings vitreous, with almost pellucid 

 neuration, some of the longitudinal uervures being sometimes very faintly amber- 

 tinted. 



$ . Very similar to the 6 . Vertex of head and pronotum pale ; the mesothoracic 

 sutures in front of the wing-roots yellow-ochreous. Venter paler than in the 6 ; 

 segments 2-7 marked on each side with a black dot beside the spu-acle, and each with 

 large twin acute obtriangular light subochraceous spots enclosing a chaKce-shaped or 

 cup-like purple-brown spot in the vicinage of the ganglion (often obliterated when, 

 dried). Setse ochroleucous, pui-ple-brown at the roots. Eore tarsus dusky, with the 

 tips of the joints black ; hinder tarsi very narrowly edged at the joinings with reddish ; 

 the terminal joint and ungues dusky. Length of body or wing 12-13 ; setse, 6 im. 27, 

 subini. 12, ? im. 20 mm. 



Sab. Western Europe, from Holland to Southern France ; Arnliem, Vasserbeck (Van 

 Medenbach de Rooy) ; South Holland (Van Walcheren) ; Rotterdam (Fransen) ; Amboise 

 (Lelievre) ; Saxony (Rostock) ; Mariensee (5th September, M'Lach. Mus.). Also 

 Toulouse ; common at gas-lamps at the lower extremity of tlie lie du Grand Eamier by 

 the Pont suspendu de St. Michel (l7-20th July) ; iu flight after sunset near the Pont 

 d'Empalot (3rd September). 



