KONGL. SV. VET. AKADEMIENS IIANDLINGAK. BAND. 20. N:0 5. 75 



Alaria oblonga. Monostroma lubricum, 



Laminaria Agardhii? » leptodennum, 



» atvofulva, Rhizoclonium pachyderraum, 



» nigripes, Chaätoinorpha Wormskioldii, 



Scytosiphon attenuatus, Ulothrix discifera, 



Phloeospora pumila, Characium marinuin, 



Dictyosiphon coryinbosus, Chlorochytriuin inclusiun, 



» hispidus, Chlorangium marinuin, 



Gleothainnion palmelloides, Riviilaria laicroscopica, 



Cha3tophora maritima, Gleocapsa spec? 



Thus: 



Floridea3 14 species representing 7 families, 9 genera, 



Fucoideaj 13(12) » » 5 » 7 » 



ChlorophyllophyceaB 9 » » 5 » 8 » 



NostochineaB 2 » » 2 » 2 » 



Total sum 38(37) species representing 19 families, 26 genera. 



The number of endemic species, 38 or perhaps only 37, is about 22 per cent of 



the total number of species of the Flora. The following table presents the outlines of 

 the distribution of the arctic Flora: 





Species 

 occurriiig on the 

 north coast of 

 Norway, besides 

 in the region of 

 the arctic Flora. 



Species 

 occurring botli 

 iu the northern 



part of the 



Atlantic anJ iu 



the Doi-thern part 



of the Pacific. 



Species knowD 



ouly from the 



uortheru 



Atlantic. 



Species kuown 



ouly from the 



uortheru Pacific. 



Species pcculiar 



to the arctic 



Flora. 



3(4) 

 2 



20 (26) 

 20 (23) 

 11 



17 (18) 

 22 (24) 

 15 



5 



4 

 3 



14 



13 (12) 

 9 



2 



FucoidecC . _ - 





Nostochiuepe . 



Total sum 



10 (11) 



51 (00) 



00 (02) 



7 



38 (37) 



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 Avithin the glacial sea, would amount to 98 by 

 the lowest estimate. One raore species must, however, surely be addcd to these, viz. 

 Antithamnion horeale, 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 homc iu the Arctic Sea. As respccts those species which are found 



