784 



for it. During my short visit at the Shetland Isles I sought it in 

 vain, still it might possibly grow there. 



From these introductorv remarks I now pass to the proper 

 comparison of the marine algæ flora of the Færoes with that of the 

 adjacent countries. In order to make such a comparison, a list of 

 the algæ -flora of the particular countries, as correct as possible 

 and critically revised, is of course indispensable. Helgi Jonsson 

 I and have prepared a list (12), which we hope to be service- 

 able, and I have used it as a basis for the following compari- 

 son, which therefore appears somewhat altered from that of the 

 Danish issue. 



We may first consider the countries which are nearest to the 

 Færoes, that is Scotland with the Ork nev s and the Shetland 

 Isles. In Batters's recently published lists (4) of the British ma- 

 rine algæ, where these countries are treated as a whole, about 430 

 species are stated as belonging to Great Britain. Of these, 163 spe- 

 cies are also found at the Færoes. The total number will certainly 

 be considerably increased by renewed investigations, a few species 

 which I found during my short visit at the Shetland Isles, have 

 already been added, namely: Fuciis inflatiis, Sphacelaria fiircigera, 

 Prasiola crispa subsp. /na/'ina, Ulvella fiicicola and Derhesia marina^; 

 to these must be added Sphacelaria britannica which is stated by Sau- 

 vageau as found in Scotland; the total number is thus increased 

 to 169 or 79 Vo of the marine algæ of the Færoes. Of the re- 

 maining species we may certainly suppose, that the following spe- 

 cies also occur in Scotland with the Orkneys and the Shetland Is- 

 les: Chantransia efflorescens, found in South England; Chantransia 

 Alariæ found, besides at the Færoes, also at North-America, at Ice- 

 land, on the coast of Norway at Haugesund and in 1904 by myself 

 at Christianssund, and in the same year by J. Adams at Port- 

 rush in North Ireland (Journal of Botany 1904, p. 351), and which 

 probably has the same distribution as Alaria esculenta; Rhodo- 

 chorton seiriolanum which has been found in West-England; Calli- 

 thamnion scopiilorum which according to Batters' list has not 

 hitherto been found at the British Isles, but which must be sup- 

 posed to be there, if Agardh's determination of its occurrence in 

 the Mediterranean is correct; Rhododermis elegans, a variety of 



^ Batters mentions D. teniiissima as occurring in Scotland; judging from 

 a specimen kindlj' sent me bj' Mr. Batters, I think that it most likely is Der- 

 bcsia marina. 



