14 KJELLMAN, THE ALG^ OF THE ARCTIC SEA. 



denser and more numerous masses spreading over considerable tracts, thus constituting a 

 whole that is well defined from other formations. In my exposition of the marine 

 vegetation of the Murman Sea, I have described two such regions of vegetation, that 

 I have called the formations (regions) of Rhodymenia and Dictyosiphon. The former is 

 found both at Spitzbergen and at Novaya Zemlya at the depth of about three fathoms 

 and is characterized by luxuriant Rhodymenia palmata. Together with it, there occurred 

 rather abundant, Ceramium rubrum at Spitzbergen, Polyides rotundus and Sarcophyllis 

 arctica at Novaya Zemlya.^) The formation of Dictyosiphon, known from the, Murman 

 Sea in Pilzbay on the west coast of Novaya Zemlya, was found within the upper part 

 of the sublitoral zone on a bottom composed of pebbles. The predominant species was 

 a form of Dictyosiphon that I referred then hesitatingly to Dictyosiphon hippuroides, 

 but have now described below under a special name: D. corymbosus. Besides, Rhodo- 

 viela lycopodioides, Chcetopteris plumosa, Punctarin plantaginea, Monostroma Blyttii, Spon- 

 gomorpha arcta formed elements of this Flora. At several places on the coast of Spitz- 

 bergen as well as at one place in the eastern part of the Siberian Sea, I have found 

 a region of vegetation that may be said to be characterized by Fucus evanescens and 

 Rhodomela lycopodioides f. tenuissima. At Spitzbergen these were most often accompa- 

 nied by Polysiphonia arctica, Rhodymenia palmata, Halosaccion ramentaceum (with Ela- 

 chista lubrica), Chordaria flagelliformis, Sphacelaria arctica, Pylaiella litoralis, Phloeospora 

 tortilis and a few rather small specimens of Laminaria Agardhii and L. solidungida. In 

 the neighbourhood of the winter quarter of Vega on the north-eastern coast of Si- 

 beria, on gravelly and stony bottom, at the depth of 2 — 3 fathoms, the vegetation of 

 a large tract was composed of the following species: Rhodomela lycopodioides, f, tenuis- 

 sima, the most common species together with Fucus evanescens; Ahnfeltia plicata, r&ther 

 abundant; Sarcophyllis arctica, the most common Floridea, next Rhodomela lycopodioides; 

 Antithamnion boreale, Alaria elliptica, Laminaria cuneifolia, Chordaria flagelliformis, Elachista 

 fucicola, Chcetopteris plumosa, all of them scarce; Sphacelaria arctica, rather common; 

 Pylaiella litoralis, common. These facts show that the Flora of those regions of vege- 

 tation consists, for the most part, of species which are either literal on the coast of 

 Norway at the present time, or most nearly related to species that are litoral here. 

 Proceeding from the supposition, which seems to me necessary and to which I shall 

 return subsequently, that the aspect and composition of the marine vegetation on the 

 coast of Norway agreed, during the glacial period, with the present one at Spitz- 

 bergen, the conclusion clearly is that no distinct formation of Fucacece occurred 

 even at the former place at that remote time. The physical conditions changing 

 gradually, Fucacece, Rhodymenia palmata, Rhodomela lycopodioides, and other modern 

 litoral forms were able to ascend to lesser depths, to increase in number of individuals, 

 and to receive amongst themselves forms of more southern origin, thus constituting 

 denser, well-defined masses, in short, to unite into the present formation of Fucaceae. 

 Under this supposition, the above-mentioned formations in the purely arctic parts of 

 the Polar Sea, composed of Fucus, Rhodymenia, Dictyosiphon, and Rhodomela, together 



^) Cp. Kjellman, Algeuv, Murra. Meer, p. 67. 



