811 



about a great deal, the whimbrel perhaps most of all.« Mr. Winge 

 further states that »a great many niigratory hirds really go to the 

 Færoes, not only those that are breeding there but also many on 

 their passage north- or southward.« 



It seems to me very probable, that several, especially littoral 

 algæ have been carried across the sea by the agency of these mi- 

 gratory hirds. How easily may not the filament of a Rhizocloniiini 

 or a Bangia stick to a bird's feathers, feet or beak. These filaments 

 are, as is well known, so elastic and roll up so easily, that they may 

 readily become entangled in the feathers of a bird. A small por- 

 tion of an alga, e. g. Porphyra, Enteromorpha , Monostroma , Uha, 

 Ulothrix, Urospora or Prasiola may also easily stick to the beak or 

 the foot of a bird, and thus be carried off. It is of course only smal- 

 ler algæ as a rule, or species of which a fragment is sufficient to 

 develop new individuals, that we can suppose have been carried 

 across the sea in this way. 



As to the wind, it is certainly not incredible that small frag- 

 ments of algæ may be swept up and carried across large distances, 

 as has been shown for both organic and inorganic substances (see 

 Warming, 83, p. 678— 679^); but I think, that no great importance 

 can be assigned to the wind as a means of transporting marine algæ. 

 As to the freshwater algæ it is quite different. They often live in 

 piaces that dry up, from which they may easily be carried a long 

 way with the dust as resting cells or spores. 



But the factor of greatest importance in the distribution of the 

 marine algæ is naturally the sea currents, and in the following 

 pages we must examine which of the currents are the most impor- 

 tant in this connection. We should naturally suppose that the greatest 

 supply of fragments of algæ, resting cells or spores is furnished by the 

 countries which are nearest to the Færoes; namely 1) the coasts of 

 Ireland and Scotland, 2) the west coast of Norway and 3) Iceland. 

 Each of these countries ma^^ be examined from this point of view. 



The coasts from which first of all the immigration would be ex- 

 pected, are those of Ireland and Scotland, as they are the nearest 

 to the Færoes. 



It cannot, however, be denied that the first view of a map of 

 the currents of the Northern Atlantic is somewhat disappointing, if 

 information is expected regarding the currents of these regions, as 



*) Cp. also: Warmiiig, Eug., Den danske Planteverdens Historie efter Istiden. 

 Kjabenhavn 1904. 



Botanj' of the Færoes. 52 



