787 



As the Shetland Isles are of ahout the same size as the Faer- 

 oes and Ue nearest to the latter (the distance is almost 300 kilo- 

 meters), a comparison between the marine algae -llora of these two 

 groups of islands would be particularly interesting. It is therefore 

 to be regretted, that the marine algse-vegelation of the Shetland Isles 

 has been but little investigated. The most important contribution to 

 our knowledge of these algae is to be found in Ed m on s ton's Flora 

 of the Shetland Isles (16) wath a list of the marine algae known at 

 that period. Since then no other contribution had been published, 

 so far as I know, until 1902 when I paid a short visit to the islands. 

 In a small paper (9) I have published my discoveries and added the 

 species mentioned by Edmonston. The number of species know^n 

 from the Shetland Isles is about 108, as I include Enteromorpha cla- 

 thrata and CaUithamnion tetragonum var. brachiatiim, whilst Gelidiiim 

 cartilagineiim must be left out, as it does not belong to the flora 

 of the islands. Of these 108 species, about 88 are also found 

 at the Faeroes; of Rhodophycece and Phceophycece 87 have hitherto 

 been know^n, of which 72 are common to both countries. But 

 as already emphasized by me in dealing with the flora of Scot- 

 land and adjacent islands, there is hardly any doubt, that by 

 far the greater part of the algae-species of the Faeroes will be found 

 there, especially on the islands that are the nearest. The only spe- 

 cies which have less likelihood of being found there are the above 

 mentioned 6 subarctic species, to which perhaps may be added a 

 few more, e. g. Laminaria fceroensis, Phceostroma parasiticiim etc. Of 

 the 20 species found at the Shetland Isles but not at the Faeroes we 

 must first mention Fucus serratus which is very common at the Shet- 

 land Isles but is, strangely enough, wanting at the Faeroes; the 

 other 19 are: Helminthora divaricata , Chylocladia kaliformis, Nito- 

 phylhim Bonneniaisonii, Spermothamnion Turneri, CaUithamnion te- 

 tragonum, Ceramium diaphanum, C. ciiiatum, Dilsea edulis, Aspero- 

 coccus bullosus, Myriotrichia clavceformis, Mesogloia vermicnlata, Sac- 

 corhiza bulbosa, Cutleria mnltifida, Fucus ceranoides, Acinetospora 

 pusilla, Chwtomorpha cerea, Ctadophora Hutchinsice, Dermocarpa 

 prasina and Calothrix confervicola. It is not impossible, that some 

 of these species may grow^ on the Faeroese coasts, but most of them 

 are forms from more southern countries, most likely having their 

 northern limit at the Shetland Isles. 



It appears from this, that the Faeroese algae-flora must be regarded 

 as a rather poor selection of the algae of Scotland and adjacent is- 



