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The Rhodijmenia -assocmiion is widely spread on the Fseroes. 

 It seems to prefer places where fresh water oozes from the rocks, 

 which is ver}^ common on the coasts. Even in places where small 

 waterfalls fall from vertical or beetling rocks down on the lit- 

 toral rocks, Rhodymenia grows abundantly. In such places it is of 

 course soaked in fresh water at low tide, and this alga must be 

 well adapted to resist great differences of salinity, for at high tide 

 it is more or less flooded by the sea. The specimens are well de- 

 veloped even in such places; they are only of a paler colour, which 

 perhaps indicates that circumstances are less favourable to them there. 

 I imagine that Rhodymenia scarcely stands complete drying up and 

 Rosenvinge is of the same opinion (71, p. 202). When Rhody- 

 menia, however, is found on the coasts of the Faeroes, rather far 

 up on the beach, sometimes even above the highest water mark, 

 the reason is, that it grows gregariously, and that it is always kept 

 moist at ebb tide by the fresh water oozing from the rocks. 



I have not found any description of a /?/70(i[//77e/7/a-association 

 quite agreeing with this vegetation which is so widely spread on the 

 coasts of the Faeroes. Still I feel inclined to believe that it will be 

 found to be rather common on the coasts of the North Atlantic. 

 According to Kleen (I.e. p. 9 and 17), it is probably also found in 

 Nordland. It is true that Boye (I.e. p. 28) speaks of a Rhodymenia- 

 formation on sheltered coasts growing in the AscophyUiim-Fiicus- 

 association , and on the the sheltered coasts of the Faeroes Rhody- 

 menia really often grows abundantly among and under the Fucus 

 bushes. Lastly Kj ellman mentions a sublittoral y> Rhodymenia-region« 

 (44, p. 67) on the coasts of Novaya Semlya and Spitzbergen. This 

 agrees well with the fact that many littoral algae elsewhere become 

 sublittoral in Arctic countries. According to Rosenvinge (71, p. 202), 

 it may however be found in the lowest part of the beach in Green- 

 land, but usually only in small numbers. Simmons does not men- 

 tion this association. 



Besides forming this littoral association growing on rocks, Rho- 

 dymenia makes a characteristic littoral association close to, yet 

 above the lowest water mark. On the parts of the Laminaria hy- 

 joertorea-association which grows in such shallow water that the tops 

 of the stipes rise above the surface of the sea at low tide, Rhody- 

 menia palmata is found attached to the uppermost part of the La- 

 minaria stalk, and often in such numbers, that the brown leaves 

 of the Laminarice are almost covered by the large, dark red Rhody- 



