895 



distiirbed by puffins; we noted liere 27 phanerogams and 33 mos- 

 ses; the latter being predominaiit and giving the vegetation its 

 character, while the phanerogams taken altogether could not be 

 compared in quantity and luxuriance with the mass of Festuca of 

 the puffm-Ur. 



This example will illustrate how birds may exert considerable 

 influence in selecling the piaces where they breed, and in altering 

 the vegetation on them. 



Something of the same kind happens on Myggenæsholm , the 

 nesting place of a large colony of Gannets (Siila bassana), and on 

 Kirkeboholm, where the Eiderducks (Somateria mollissima) nest. 



The other wild animals are of secondary importance so far as 

 vegetation is concerned. The rabbit (Lepiis timidiis) is not nume- 

 rons enough to play an important part. Invertebrates may also be 

 left out of account^. 



III. SOME BIOLOGICAL FEATURES. 



Before proceeding to the description of the plant-formations, it 

 may be well to notice some biologicai features of the species ap- 

 pearing therein, confining ourselves, however, to the higher piants. 

 The features dealt with in this chapter are: 



1 '^ Duration of life. 



2^ Biological types, in Raunkiær 's acceptation. 



3^ Vegetative propagation and structure of the shoots. 



4" Time of flowering. 



5*^ Maturation of fruit. 



6*^ Distribution in attitude. 



It seems advisable that I should give an alphabetical list of the 

 vascular piants which, in my opinion, are to be regarded as native 

 or as quite naturalized in the Færoes. The species listed are 

 those indicated by numbers in my supplementary floristic list 

 (Ostenfeld 1907), but I have omitted the species which are not 

 completely naturalized. 



^ As alreach' stated. cartlnvorms and other animals, including bacteria, take 

 part in the formation of monld, and hence may be regarded as indirectly impor- 

 tant for vegetation. 



