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The /?/}0(iy/rjen/a- association is widely spread on the Færoes. 

 Il seems lo prefer piaces where fresh water oozes from the rocks, 

 which is verj' common on the coasts. Even in piaces where small 

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

 toral rocks, Rhodymenia grows abundantly. In such piaces il is of 

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

 well adapled 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 piaces; they are only of a paler colour, which 

 perhaps indicates Ihat 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, how^ever, is found on the coasts of the Færoes, rather far 

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

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

 moist al ebb lide by the fresh water oozing from the rocks. 



I have not found any description of a i?/joG?ymenfa-association 

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

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

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

 According to Kieen (1. c. p. 9 and 17), it is probably also found in 

 Nordland. It is true that Boye (1. c. p. 28) speaks of a Rhodymenia- 

 formation on sheltered coasts growing in the AscophyUum-Fucus- 

 association, and on the the shellered coasts of the Færoes Rhody- 

 menia really oflen grows abundantly among and under the Fucus 

 bushes. Lastly Kj eliman menlions a sublittoral »Rhodymenia-region« 

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

 agrees well wålh the faet that many littoral algæ else where become 

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

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

 land, but usually only in small numbers. Si m mon s does not men- 

 lion this association. 



Resides forming this littoral association growång on rocks, Rho- 

 dymenia makes a characleristic littoral association close to, yet 

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

 /)erfco/-ea-association wdiich 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 slalk, and oflen in such numbers, that the brown leaves 

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



