778 



It is clear from this summary that the Rhodophyceæ are most 

 numerous, contributing almost Vs of all the species collected. The 

 Phæophyceæ are a little less numerous, aboul ^3 of all the marine 

 algæ- species of the Færoes; next come the Chlorophyceæ, which 

 only amount to a little above V5, and lastly the Cyanophyceæ, of 

 which only a few species have been collected. 



Ro se uvinge (71, p. 173) has given a summary in per centages 

 of the number of species belonging to each of the four classes of algæ, 

 as they occur in the algæ-floræ of Greenland, the British Isles and 

 in the Spanish-Canary region. If the numbers that represent these 

 groups in the Færoese algæ-flora are placed in this summary, and 

 if, at the same time, the numbers representing the Greenland algæ 

 are altered to agree with the latest contributions concerning the latter, 

 and the numbers from the British Isles are calculaled from Bat- 

 ter s's latest list (4), the result will be as follows: 



Greenland The Færoes ^'^^ ^"^ish j The Spanish- 

 ; Isles rCanarj' Reg. 



Rhodophyceæ 26.0 % 38.6 »/o 42.3 Vo \ 60.4 "/o 



Phæophyceæ j 40.0 "/o 34.0 % ; 27.8 % 18.7 «/o 



Chlorophyceæ 30.0% I 20.9 7o ! 17.9 7o , 14.8 7o 



Cyanophyceæ 1 6.0 7o 6.5 «/o 12.0 "/o 6.1 Vo 



II J \ \ 



Total number of species. . [i 169 215 744 492 



As clearly shown by the figures, the Færoes hold an inter- 

 mediate position between Greenland and the British Isles; Ihe Rhodo- 

 phyceæ, which are in the majority in England, to say nolhing of 

 the Spanish-Canary region, are still predominant on the Færoese 

 coasts; whereas the Phæophyceæ, which are vastly in the majority 

 in Greenland almost reach to the same number. 



The Chlorophyceæ likewise hold an intermediate position as 

 regards number of species between the British Isles and Greenland, 

 where they are relatively more numerous; the same may be said 

 of the Cyanophyceæ, only inversely, as these are more numerous in 

 the British Isles and less numerous in Greenland. That only a re- 

 latively small number of the latter have been found in the Spanish- • 

 Canary region, is certainly due to the faet that this region (as regards 

 the Cyanophyceæ) has hitherto been but very little investigated. 



It is, on the whole, a well-known faet that the Phæophyceæ 



