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flows into the sea liere, which is therefore often very brackish, and 

 at certain piaces almost fresh. Even at the mouths of the large 

 effluents only Enteromorpha intestinalis and a few Ectocarpiis litoralis 

 are found, but at a short distance from the exit specimens of Fiiciis, 

 Enteromorpha ckiihrata, Ceramium rubrum and others. 



Thus it is evident, and examples can be met with everywhere 

 in the Færoes, that in passing from exposed to sheltered coasts 

 the flora of these two localitics will be found to vary greatly. 

 Further illustration of this will be given in the section concerning 

 communities of algæ. 



Flowing or stagnant water are likewise of great importance to 

 the algal vegetation and give it a widely varying character. The 

 current constantly carries fresh sea-water, and thus new nutritive 

 substances, to the algæ, whereas the vital functions must naturally 

 proceed more slowly in stagnant water, where the supply of fresh 

 sea-water is much smaller. If we examine the same forms of algal 

 vegetation, e. g. the Laminaria hyperborea-associaiion, we likewise 

 find it much more vigorously developed than in piaces where the 

 Avater is stagnant. Most likely this is also due to the mechanical 

 influence of the current; at any rate we find a very well developed 

 algal vegetation in piaces where there are rapid currents. 



Just as a current causes fresh-water piants to become elongated, 

 many algæ growing in piaces much exposed to currents have long 

 and rather narrow fronds. I have seen very fine examples of this 

 at Gotebue near Mjovenæs on Ostero, on dredging in ca. 10 fathoms 

 of water. Here a Laminaria hyperborea -asaociaiion was found, in 

 which the main plant was strong and robust, but the lamina had 

 narrow laps; and growing epiphytically on this, were some Deles- 

 seria alata a foot in length, and some still longer Delesseria sinuosa 

 and Odonthalia dentata, all with very narrow fronds. On the other 

 band, the thallus of other species e. g. Euthora cristata and Rhodo- 

 phyllis dichotoma was broad and robust in this place as elsewhere 

 in rapid currents and on exposed coasts. 



The same species of algæ is often very different in its appear- 

 ance according to its habitat. Thus it seems, that many algæ in 

 sheltered piaces are inclined to form proliferations, that is, long, 

 thin appendages from the otherwise broad thallus; fine examples 

 of this are shown by Delesseria sinuosa, which in sheltered piaces 

 has a peculiar form, f. lingulata, remarkable for its numerous 

 narrow proliferations, and Enteromorpha intestinalis, a variety of 



