MARINE ALGAL VEGETATION 71 



same figures as for E. Iceland, and on combining NW., SW. and 

 S. Iceland we get almost the same figures as for SW. Iceland. E. 

 Iceland and N. Iceland have 101 species of red and brown algas 

 collectively. Of these 8 (8 %) are arctic, 20 (20 %) subarctic (sub- 

 division I), 28 (27 %>) subarctic (subdivision II), 17 (17 o) boreal- 

 arctic, 26 (26 %) cold-boreal and 2 (2 %>) warm-boreal. NW., SW. 

 and S. Iceland have 131 species of red and brown algae collectively. 

 Of these 3 (2%) are arctic, 20 (15%) subarctic (subdivision I), 29 

 (22 %) subarctic (subdivision II), 16 (12 /o) boreal-arctic, 53 (41 /o) 

 cold-boreal and 10 (8 %) warm-boreal. 



As regards the components of the flora, both Iceland taken as 

 a whole, and SW. Iceland resemble Finmark; S. Iceland resembles 

 the Faeroes and Nordland, and E. Iceland resembles the White Sea. 1 



It is evidently not due to chance that the resemblance of the 



/ 



floral districts happens thus. The situation of Iceland just south of 

 and at the boundary between the arctic and the cold-boreal districts 

 corresponds exactly with the situation of Nordland Finmark- -White 

 Sea in relation to this boundary. Iceland and the White Sea are 

 at the boundary itself, and in Finmark it certainly will be possible 

 to distinguish parts of the coast w r ith a similar mixed flora as in 

 N. and NW. Iceland; the southern part of Finmark will then be 

 something like SW. Iceland, while S. Iceland, as already mentioned, 

 corresponds with Nordland. 



This comparison shows only the relation between the quantity 

 of the species of the floral districts within the different groups, but 

 gives no information as to how far the species are common to all 

 those districts. Then it remains to be investigated how many species 

 Iceland has in common with the other districts. At the present 

 time a comparison of the floras will, however, scarcely give any 

 satisfactory results, because all the districts in question are not 

 equally well-known. By future investigations a greater number of 

 species will unquestionably be found in the majority of the floral 

 districts, and the quantity of the species will thus be altered, but 

 the relation between the number of the species of the different 

 groups will, how r ever, undoubtedly remain unaltered. 



1 According to Borgesen and Jonsson (14) 52 species are known from the 

 White Sea, of which 3 '6 %>) are arctic, 10 19 %>) subarctic (subdivision I), 19 

 (37/o) subarctic (subdivision II), 8 (15 %) boreal-arctic and 12 (23%) cold-boreal. 

 The subarctic species constitute 56 % of the entire number of species and the 

 character of the flora is consequently subarctic in the same degree as that of E 

 Iceland. 



