572 EPHE MERINO. 



Genus 5. CLOEON. 



Oculi maris duplices. Pedes bene determinati. Setae caudales 

 duse. Ala? quatuor, venis transversis paucis. Larva natans, non 

 subiens, cauda \alde ciliata. 



Ephemera, Linn. ; De Vill. ; Fabr. ; Gmel. ; Oliv. ; Schr. ,• Walkn. ; 



Latr. ; Stew. ; Turt. ; Guer. ; Zett. ; Blanch, 

 Cloeon, Leach ; Steph. ; Curt. 

 Cloe, Burm. Handb. Ent. ii. 2 ; Pictet ; Ramb. 

 Baetis, p., Steph. 

 Oxycypha, p., Burm. 



Each of the ordinary eyes of the male surmounted by a great 

 reticulated eye in the form of a turban, that is supported on an ob- 

 conical ring at whose base is the ordinary eye : wings two or four ; 

 fore-wings having only very few cross-veins which generally form two 

 crooked lines : lower wings, when they exist, rudimentary, and with 

 a more or less incomplete neuration : abdominal tentacula rather 

 large ; internal appendages short, conical : two tail-bristles with a 

 very little rudiment of the median one. 



A. Alee quatuor. 

 1. Cloeon bioculata. 



Maris uculi obscuri ; mesothorax flavus unicolor ; abdomen basi 

 apiceque obscurum, apud medium pallidius ; alee non fasciatw 

 nee maculatce. 



Ephemera bioculata, Linn. Hist. Nat. Ed. 12, ii. 906, 5. De Vill. 

 Linn. Ent. iii. 18, 7. Oliv. Enc. Meth. vi. 419, 10. Fabr. 

 Ent. Syst. ii. 70, 9. Gmel. Ed. Syst. Nat. i.2629, 5. Barbut, 

 Gen. pi. 11, fig. inf. sinist. ? Steiv. El. Nat. Hist. ii. 211. 

 Turt. Syst. Nat. iii. 394. Walkn. Faun. Par. ii. 9, 6. Panz. 

 Faun. xciv. fig. 17. Latr. Hist. Nat. Ins. xiii. 97? Guer. 

 Icon. Regne Anim. Ins. PL 60. Zett. Ins. Lapp. 1044, 9. 

 Blanch. Hist. Nat. Ins. iii. 64, 6. 



