1008 



between Ihem. Since these formations all are so closely related, 

 \ve may suppose thai development trom one to the other has pro- 

 ceeded in several directions. 



An attempt is made here in the accompanying diagram to illus- 

 trate their relationship and the mode of development, and it shows 

 at once how much tliey are interlinked. 



4. The vegetation of the sea-fowl oliffs. 



Special reference ought to be made to that vegetation found 

 about the nesting-places of the countless colonies of sea-fowl — 

 auks (Alcidae), sea-gulls (Lams spp., especially L. tridactyhis), cor- 

 morants (Phalacrocoraæ spp.) and fulmar petreis (Fiilmarus glacialis) 

 (see also p. 894). 



Piaces of this kind are unsuited to the growth of many species 

 on account of the acrid excrements of the sea-fowi, but on the 

 other hånd cerlain species are favoured by the abundance of nitro- 

 genous matter present. There is thus what might be called a cul- 

 ti vation of the soil, as a result of the operations of the hirds. For 

 this reason I have reserved this vegetation to the end of the series 

 of natural formations, thus indicating its approach to the forma- 

 tions of the cultivated area. It must, however, be regarded as so 

 far natural in that the »cultivation« consists merely in a change in 

 the natural condition of the soil due to the excrements of the birds, 

 and is not the result of methodical treatment. 



The sea-fowl cliffs are almost inaccessible to man, and to be 

 able to traverse them, as the fowlers do, requires that life-long 

 experience from childhood onwards, so often spoken of in legends 

 and folklore. A stranger visiting the Færoes for one short summer 

 has no such experience, and this combined with the faet that the other 

 vegetation gave me quite enough to do, is my apology for these 

 fragmentary and scanty notes on the sea-fowl cliffs. They certainly 

 deserve a more thorough investigation. 



Most of the sea-fowl, which form the colonies, nest on ex- 

 tremely narrow shelves on vertical cliffs facing the sea. There they 

 sit, side by side, in countless numbers. Scarcely a vestige of vege- 

 tation can be found in such piaces, except perhaps an odd rock- 

 plant here and there in some crevice. The piants which appear 

 here are those found generally in crevices, but more especially those 

 of the sea-cliffs (see p. 931). One plant, however, is met with in its 



