534 EPHEMERIN^E. 



larva in form, habit and food. Rudiments of wings very percepti- 

 ble at the posterior angles of the wing-bearing segments. Attains 

 its perfect state by a double ecdysis ; after the first, the insect re- 

 tains the soft, silky pellicle which invests a great number of insects, 

 and which, in all other cases, is shed with the pupa-case. After a 

 feeble flight the insect settles, and in the course of a few hours di- 

 vests itself of the pellicle, and has then accomplished all its trans- 

 formations.'' — Newman. 



Genus 1. EPHEMERA. 



Oculi remoti, maris simplices. Pedes bene determinati. Setae 

 caudales tres, asquales. Alae reticulata?, quatuor, venis plurimis 

 transversis. Larva subiens, instrumentis respiratoriis quasi amen- 

 tales. 



Ephemera, Linn., fyc. 

 Ephemeras trisetae, p., Zett. 

 Ephemeridae, p., Newman. 



Eyes simple in both sexes, always separated by a broad interval : 

 wings four, with numerous cross-veins ; hind-wings almost as long 

 as one-fourth of the fore-wings, with a complete neuration and an 

 angular costal border : abdominal tentaculae of middle size ; inter- 

 nal appendages hidden, very small: three tail-bristles of equal 

 length. 



1. Ephemera vulgata. 



Obscure fusca ; abdomen lutescens ; seta caudales nigricantes ; 

 pedes pallidi, obscure nebulosi ; ala fuscescentes, anticce costa 

 pallida fusca, maculis tribus vel quatuor, posticce maris ma- 

 cula media. 



Ephemera vulgata, Linn. Si/st. Nat. Ed. 12, ii. 906, 1. Fauna 

 Suecica, 1472, 1. Geoff r. Hist. Ins. ii. 238, 1. Scop. Ent. 

 Cam. 264, 683. Schaff. Elem. pi. 72. Deg. Ins. ii. 621, pi. 

 16. Mull. Prod. Zool. Dan. 142, 1641. Sulz. Ins. fig. 103. 

 Mas. Lesk. i. 50, 13. Schrank, Ins. Austr. 602 ; Faun. Boic. 

 1937. Gmel. Ed. Si/st. Nat. i. 5, 2678, 1. Barbut, Gen. 213, 



