800 



Agariim Tiirneri, Chlorochijtrinm Schmitzii, Ulothrix siibflaccida, 

 Acrochcvte parasitica, Urospora Barlzii, Rhizocloniiim pachyderiniim^, 

 Acrosiphonia penicilliforme ; 22 species in all. 



Subdivision 2: Pha^ostroma pustiilosiim , Haplospora globosa, 

 Chlorochijtriam Cohnii, Ch. dermatocolax , Cladophora hirta; 5 spe- 

 cies in all. 



The 1)0 real-arctic group: Chantransia microscopica, Oscilla- 

 toria amphibia, 0. tenuis^; 3 species in all. 



The cold -boreal group: Lithothamnion intermedium, Ecto- 

 carpus Pringsheimii,' E. penicillatus, Sphacelaria radicans, Dictyosiphon 

 Chordaria, Epicladia Fhistrce, Ochlochcete ferox, Vaucheria intermedia, 

 V. sphcerospora ; 9 species in all. 



Thus we see, that by far the greater part of these species be- 

 longs to the arctic and the coldest subdivision of the subarctic group; 

 it is not probable that any of these species will be found at the 

 Fseroes. On the other hand, some of the few species referred to 

 the other groups will no doubt be found to grow there. 



This comparison thus leads to the conclusion that the Faeroese 

 algae-tlora includes a great number of southern forms wanting at 

 Greenland, whilst Greenland has a great number of arctic species 

 not found at the Faeroes. 



Lastly we may make a comparison with the algae -flora of 

 North-America. It is a well-known fact that in spite of the 

 great distance separating the algae -flora of North- Europe from 

 that of the North-American coast of the North-Atlantic Ocean, they 

 still have a great many species in common. Our knowledge of 

 the North -American algae -flora we owe firstly to Far low's well- 

 known paper (20) which is now somewhat antiquated, however, 

 as it is 25 years since it was published, secondly to later works of 

 Far low, Collins and others. The latter author published in 1900 

 a list (13) of the North-American algae, which has been used toge- 

 ther with Farlow's above-mentioned paper as a basis for this 

 comparison. Of the species mentioned in this list about 130 are 

 also found at the Faeroes, that is, more than one half (60 ^/o) of 

 all the Faeroese species. Farlow has already called our attention 

 to the great resemblance between the algae-flora of both sides of 

 the North- Atlantic Ocean ; he likewise mentions (20, p. 4) some of 

 the commonest species that grow both east and west of the Ocean. 



^ Found in freshwater at the Faeroes. 



