KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND. 20. N:o 5. | 
we 
Ptilota plumosa (L.) Ag. 
Syn. Alg. p. 39, excl. @. Fucus plumosus L. Mant. p. 134. 
Descr. VPtilota plumosa J G. Ac. Kpicr. p. 75. 
Fig. » » Harv. Phyc. Brit. t. 80. 
Ewsice. > » Aruscu. Alg. Scand. exsicc. N:o 160. 
Syn. Fucus plumosus R. Br. in Scokessy, Account., 1, p. 152 et append V? Nonne Pt. pectinata: 
» » Gonn. FI. Norv. 2, p. 91. 
» » a et @ Wea. Fl. Lapp. p. 501. 
» ptilotus Gunn. Fl. Norv. 2, p. 135. 
Plumaria pectinata var. tenerrima Rupr. Alg. Och. p. 336. 
Ptilota plumosa J. G. Ac. Spetsb. Alg. Progr. p. 3; Bidr. p. 11 
» » Argscu. Phye. Scand. p. 319. 
» » a typica Gopi, Algenfl. Weiss. Meer. p. 44. 
» » Harv. Ner. Am. 2, p. 224. 
» » KseLim. Spetsb. Thall. 1, p. 26; Algenv. Murm. Meer. p. 22. 
» » Kueen, Nordl. Alg. p. 20. 
» » Lynes. Hydr. Dan. p. 38. 
» » var. tenuissima ScuUBELER in LHeugl. Reise, p. 517. 
» » Wirrr. in Heugl. Reise, p. 284. 
Halitat. This species is generally sublitoral, occurring in 5—20 fathoms water 
on stony or pebbly bottom. Sometimes it is found in more shallow water, even within 
the litoral zone in rock-pools between tides. It is attached sometimes to other algi, 
usually to stones, and grows on exposed coasts as well as in the interior of bays and 
at other sheltered places. I never found it gregarious. On the coasts of Spitzbergen 
and Novaya Zemlya it usually constitutes an element of the Laminariacie-formation; on 
the west coast of Norway I have generally found it in company with purely arctic 
alew. Here it attains a high degree of luxuriancy. The largest specimens I ever 
saw, from the interior of Altenfjord, had a length of 20—25 cm. The plant has not 
been examined in winter in the Polar Sea. Individuals with sporocarps have been 
found at Nordlanden in July and August, at Finmarken at the end of August and in 
the earlier part of September, at Spitzbergen in July, on the west coast of Novaya 
Zemlya and Waygats in August and at the end of June. Specimens with tetrasporangia 
have been collected in most of these parts of the Arctic Sea in July and August. 
Geogr. Distrib. The present species belongs both to the Atlantic and the arctic 
region of the Polar Sea, having its maximum of frequency within the former. Its most 
northerly known locality is the outer Norse Island off the north-western coast of Spitz- 
bergen Lat. N. 79° 50’. 
Localities: The Norwegian Polar Sea: Nordlanden, common and plentiful; Fin- 
marken: Maasé, Gjesver, Magerd Sound, Oxfjord, and Talvik, abundant, but local. 
The Greenland Sea: According to my experience, local and scanty on the coasts 
of Spitzbergen. 
The Murman Sea: the coast of Cisuralian Samoyede-land; the west coast of No- 
vaya Zemlya and Waygats from Matotshin Shar to Jugor Shar, pretty common and 
abundant. 
