KONGL. SV. VET. AKADEMIENS IIANULINGAU. BAND. 20. W.O 5. 



75 



Alaria oblonga. 

 Laminaria Agardhii? 



» atrofulva, 



» nigripes, 



Scytosiphon attenuatus, 

 Phloeospora pumila, 

 Dictyosiphon corymbosus, 



» hispidus, 



Gleothainnion palmelloides, 

 Chsetophora maritima, 



Thus: 



Florideae 14 species 



Fucoidese 13(12) » 



ChlorophyllophyceEe 9 » 



Nostochineae 2 » 



Total sum 38(37) species 



The number of endemic species, 38 

 the total number of species of the Flora, 

 the distribution of the arctic Flora: 



Monostroma lubricum, 



» leptodermum, 



Rhizoclonium pachydermum, 

 Chaatomorpha Wormskioldii, 

 Ulothrix discifera, 

 Characium marinum, 

 Chlorochytrium inclusum, 

 Chlorangium marinum, 

 Rivularia microscopica, 

 Gleocapsa spec? 



representing 7 families, 9 genera, 



» 5 » 7 » 



» 5 » 8 » 



» 2 » 2 » 



representing 19 families, 26 genera. 



or perhaps only 37, is about 22 per cent of 

 The following table presents the outlines of 



If we assume, that the Arctic Sea has been the centre of development not only 

 of the endemic species, but also of those species which the arctic Flora has in common 

 with the northern Atlantic and the northern Pacific, and besides of those species which 

 are known from the Polar Sea on the coast of Norway at the same time as from the 

 Arctic region proper, the number of arctic species that may be considered on good 

 grounds to have developed themselves within the glacial sea, would amount to 98 by 

 the lowest estimate. One more species must, however, surely be added to these, viz. 

 Antithamnion boreale, known from the north coast of Norway and the northern part of the 

 Pacific. Besides, I believe it can hardly be doubted with regard to those 7 species which 

 the arctic Flora has in common with the northern part of the Pacific, that all except one 

 have their original .home in the Arctic Sea, As respects those species which are found 



