104 



the division by drawing a line from Toftevatn on Sonth-Ostero to 

 Sydredal on Stromo and from thence to Sorvaagsvatn on Vaago, 

 thereby cutting off the southern end of these three istands and including 

 them in the southern section. My reason for this is, partly that these 

 parts being low and having a more rounded form correspond more 

 closely to Sando and Sydero than to the northern parts of Stromo, 

 Ostero and Vaago; partly that several of the species wliich occur 

 on tlie soiitliern islands have been proved to extend to these parts, 

 but not farther north. 



The mountains of the northern section are on an average 

 higher and more precipitous (Fig. 6) and the intervening areas of 

 low-lying lands are fewer, so that hill piants {Ardic^) are naturally 

 far more common here than in the southern section. The most im- 

 portant of these species which characterize the northern section, 

 but are absent (or rarely found *) in the southern section, are the 

 foUowing: — 



Campanula rotundifolia. Dryas octopetala. 



Gnaphalium supinum, rc.^ Potentitla verna. 



"'' Loiseleuria procumbens, re. Sibbaidia procumbens, re. 



Euphrasia tatifolia. Saxifraga rivutaris, re. 



Veronica alpina. Salix glauca. 



Pyrola minor. Luzula arcuata, re. 



Cerastium atpinnm. Carex atrata. 



— trigynum. * — rigida, re. 



Sagina nivalis, re. * — saxatilis, re. 



Ranunculus glaciatis, re. Aspidium Lonchitis. 



Papaver radicatum. 



All the above-mentioned 21 species are hill piants {Campanula 

 rotundifolia — at least on Bord 6 — and Pyrola minor also appear here 

 as hill piants) and those marked re are fairly common in the high 

 lands. Besides these hill piants, several lowland piants {Temperate 

 European and Atlantic) have been found in the northern section, 

 near Ejde on Ostero and thence along Sundelaget, which either have 

 not been found in other piaces on the islands — such as Myosotis 

 palustris and Galium palustre — or are more common in the southern 

 section — as Scilla verna, Chamænerium cmgustifolium, Potamogeton 

 natans and pusillus as well as Iris Pseudacorus. This is doubtless 



^ For the defination of the terms »Arclic«, iTemperate European«, ^ Atlantic^ 

 see below p. 110. 



2 re = rather common. 



