30 EEV. A. E. EATON ON EECENT EPHEMEEID^ OE MAYFLIES. 



tarsus is minutely spinulose beneath ; the hind tibia is similarly spinulose behind dis- 

 tally ; the tibia and tarsi are all slender, and the femora distally somewhat enlarged ; 

 the tracheal laminae are spinulose also. Head semielliptical, arched above from side to 

 side, and shelving from behind, so as to be wedge-like in vertical section, the underside 

 being flattened. Antennae glabrous, setaceous, the first two joints the largest. Labrum 

 sbghtly retuse in front, and diffusely pilose along its anterior border. Mandibles distally 

 enlarged, the molar tuberosity continuous with the crown, compact, and relatively large ; 

 the three fangs slender and small, the innermost appendiculated. Lacinia of 1st maxillaj 

 small, ovate lanceolate, pungent, densely bearded inside, pubescent outside ; the palpus 

 very large and stout, the first joint minute, pubescent outside ; the second joint rela- 

 tively enormous, finger-like, curved, tapering distally, within and without at the tip 

 densely hairy above, more sparsely pubescent beneath ; the stipes closely associated with 

 the fan-like branchial tuft of fibrils, which passes backwards above and beyond the 

 hinder border of the labium, and underlies the prosternuni. Lacinige of the 2nd maxillae 

 (if developed at all) adherent to the labium in the form of two elevated folds of mem- 

 brane ; palpus strong and finger-like, the first joint short, pilose ; second joint pubescent, 

 long, and stout. Lingua somewhat broadly cordate ; the paraglosste well developed and 

 somewhat rounded. Outer seta? less than half as long as the body. 



Distribution. Europe, middle and south, and Brazil. 



Ti/pe. 0. anomala, Pict. 



Mijmology . oXlyoc and vevglov, from the paucity of cross veinlets in the wings. 



The following differences between the adult European and Brazilian species may here 

 be noted, because they may be accompanied by unconformity in the nymphs, and be of 

 more than specific value. O. anomala, ? , has the setae equal to each other in length, 

 and sparingly pilose. The d has the fore tibia relatively shorter in proportion to the 

 femur than 0. rhenana, and the proximal joint in all the tarsi longer than the second 

 joint. In O. rhenana, ? , the intermediate seta is slightly shorter than the outer setae, 

 and all are glabrous. The 6 fore tibia is about 1-| (instead of only 1^) as long as the 

 femur, and the proximal joint in all the tarsi is shorter than the second joint. 



Oligoneubia anomala, Pict. Plate III. 2 i ( d , wings, legs, and forceps, $ , legs). 



Oligoneuria [type] anomala, Pict., Hist. Nat. Nevropt. ii. Epli^m. 290, pi. xlvii. (1843-5) ; Walk., 

 List Neuropt. in Brit. Mus. part iii. 585 (1853) ; Hag., Stct. ent. Zeit. xvi. 269, pi. i. (1855) ; Etn., Ent. 

 Mo. Mag. V. 83 (1868); id., Trans. Ent. Soc. London (1871), 55. 



Adult {dried) <s . — Wings transparent light sepia-grey, with opaque light pitch-brown 

 longitudinal neuration, the membrane giving a dull light purple-grey reflection. Thorax 

 pitch-brown. Abdomen in segments 8-10 and in the distal halves of segments 2-7 

 pitch-brown, the anterior halves of these being pellucid white. Setae warm sepia-grey, 

 with alternately wide and narrow light pitch-brown annulations at the joinings. Legs 

 subpiceous, the hinder tarsi with their terminal joint white, and ungues piceous. 



? (after Ilagen). Body fuscous or brown. Wings light grey, the fore wings with 

 about six cross veinlets [in the space beliind nervure uo. 3j. Length of body, 6 , about 7, 

 $ (Hagen) 13 ; wing, cJ 8, ? 15 ; setae, ? 8 mm. 



