14 ARKIV FÖR ZOOLOGI. BAND 7. N:0 30. 



opinion is also favoured in tbe diagnosis by the words »alis 

 hyalinis», where no spöts are mentioned. As to the spread 

 it is only stated, as for most of the other species, »in Europas 

 aquis». This does not, however, exclude the occurrence of 

 the species also in Scandinavia, and therefore the species in 

 question also could be determined as Ephemera glaucops 

 Ptct. It seems to me that in support of this interpretation 

 could also be stated the sequence, in which the species is 

 given both by Linné and by Fabricius, and in which the 

 idea of the affinity of the species finds expression to a cer- 

 tain degree. This sequence seems, as regards the section 

 »cäuda triseta», have been based upon the size of the species, 

 and the fact that lutea by both the mentioned authors is 

 placed immediately after the greatest species, E. ndgata, 

 sliould, in my opinion, suggest that E. glaucops Pict. and 

 not the smaller Potamanthiis luteus auct., which is inferio r 

 in size also to the following species, warginata, has been in- 

 tended in the description. Add to this that the spöts of the 

 wings, at least of Swedish specimens, are, especially in 

 comparison wuth vulgata rather slightly marked, and it seems 

 to me, that such an opinion is not at all improbable. 



3. Eph. inarginata (1. c. pag. 69. N:o 4) is Leptophlebia 

 marginata auct., as I have tried to show above (see Linné's 

 species N:o 2). 



4. Eph. vespertina (1. c. pag. 69. N:o 5) is without doubt 

 the same species as Linné's vespertina (see that species). 



5. Eph. halierata (1. c. pag. 69. N:o 6). — Eaton inter- 

 preted this species at first (Monogr. on Ephem. Träns. Entom. 

 Soc. 1871 p. 87) as identical with »Leptophlebia cincta^RETZ.», 

 which opinion he seems to have based upon Fabricius' 

 quotation of De Geer's species N:o 3. This determination 

 is, however, obviously wrong, as several of the characters, 

 mentioned by Fabricius, as »alse duse, margine crassiore 

 nigricante», »cauda setis . . . corpore quadruplo longioribus», 

 are decidedly at variance both with the description and with 

 the illustrations by De Geer. Hagen's ' Identification of it 

 with a Ccenis Steph. has Eaton- låter on accepted and de- 

 termined it as Ccenis macrura Steph. It seems to me, that 



^ Notes on the Ephemerida?. Träns. Ent. Soc. London 1873. p. 39G. 

 " Revis. Monogr. p. 144. 



