CHAPTER XX. 



THE family of the Ephemeridce comprises various genera 

 and species, and offers peculiar attractions to the fly-fisher. 

 Stephens (" Illustration of British Entomology," vol. vi., 

 1835) gives the British genera in the following order : 



I, Ephemera, with 1 6 species ; 2, Ccem's, J species ; 

 3, Bae'tis, 1 8 species ; 4, Cloeon, 8 species. 



Pictet (" Hist. Nat. des Insectes Neuropteres," 1843) 

 gives seven genera of the Ephemeridce, five of which are 

 British, viz. : 



I, Ephemera, 2 species ; 2, Bae'tis, 5 species ; 3, Potoman- 

 thus, 3 species; 4, Cloeon, 3 species; 5, Ccem's, 2 species. 



Eaton ("A Revisional Monograph of Recent Ephemeridae 

 or May -flies," 18834-5) gives twelve genera, viz. : 



I, Ephemera, 3 species ; 2, Potomanthus, I specie ; 

 3, Leptophlebia, 2 species ; 4, Harbrophlebia, I specie ; 

 5, Ephemerella, I specie ; 6, Ccem's, 3 species ; 7, Bae'tis, 

 9 species ; 8, Centrophelum, 2 species ; 9, Cloeon, 3 species ; 

 10, Siphhirus, 2 species ; 1 1, Nithrogenia, I specie; 12, 

 Heplagenia, 2 species. 



Most of these new species of Eaton's have been recog- 

 nised both by Stephens and Pictet, only under different 

 names, and placed generally in Bae'tis and Cloeon. 



The author of the article " Ephemeridce in the " Ency- 

 clopaedia Britannica" (vol. viii.) places this family in the 

 Pseudo-Nenroptera, a sub-order of the Orthoptera, having 

 the metamorphosis incomplete. He says : " The Ephemeridce, 

 a remarkable group of pseudo-neuropterous insects deriving 

 the name from e^/xepo?, in allusion to the very short lives 

 of the winged insects. In some species it is possible that 

 they have scarcely more than one day's existence ; but 



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