707 



II. 



ALGÆ-REGIONS AND ALGÆ- FORMATIONS ON THE COASTS 



OF THE FÆROES. 



In his well-known paper on the algæ- flora of the Murmann 

 Sea (44, p. 57) Kjell man divides the flora: »in drei Gebiete und 

 zwar in das litorale, sublitorale und elitorale«. By littoral »Gebiet« 

 he means the part of the bottom of the sea which is left dry by 

 the ebb of the spring tide, that is, from the highest tide mark to 

 the lowest ebb mark. The sublittoral »Gebiet« extends from di- 

 rectly below the littoral »Gebiet« down to a depth of 20 fathoms, 

 and finally the elittoral »Gebiet« consists of the bottom lying below 

 yet overgrown by algæ. In a later paper (45) on the algæ -flora of 

 the Skagerak, Kjell man introduces the name »region« instead of 

 »Gebiet«. He asserts that the limit betwcen the two first named 

 regions is distinct and natural. The vegetation of the littoral region 

 is essentially difterent from that of the sublittoral region, evidently 

 a natural consequence of the very difterent local circumstances pre- 

 vailing in each of these two regions. The limit between the sub- 

 littoral and the ehttoral regions is, however, less distinct. 



With more or less variation of the limits of these regions, later 

 authors have used this division by Kjellman as a basis for their 

 division of the algæ -vegetation of other tracts of the sea. I shall 

 do the same, with some alterations. 



Smaller types of vegetation belonging to the algæ -regions are 

 named »Algenformationen« by Kjellman (45, p. 10); his definition 

 is as follows: »Unter einer Algenformation sollte folglich ein Ab- 

 schitt der ganzen Algenvegetation verstanden werden , der durch 

 ein eigenthiimliches Vegetations-Gepråge ausgezeichnet ist. Im All- 

 gemeinen erhalten diese Abschnitte dadurch dieses Gepråge, dass 

 eine oder einige Algenarten die Hauptmasse ihrer Bestandtheile 

 ausmachen.« 



I propose the name of association for these types of vegeta- 

 tion. These associations are often united in a natural way in larger 

 communities, where they live together under the same or very si- 

 milar biologicai and ecological conditions. I propose the name of 

 formation for these more comprehensive groups. If any further 

 subdivision is particularly wanted, we may use the word facies, 



