Contribution. I. 41 



the litoral zone it generally occurs on steep rocks covered 

 by other algae, as Fucus and Osothallia, or on the walls of 

 grotto-shape'd cavities most often together with Delesseria 

 alata. It is only to be found on open shore and best devel- 

 oped in much exposed localities. Even as far eastward as 

 at Vardo I have seen very luxuriant individuals about 15 

 cm. high. However it is most commonly smaller, 4 — 8 cm. 

 Specimens bearing only few tetrasporangia have been collec- 

 ted in the later half of July and in the earlier half of Au- 

 gust. 



Distribution: Pretty common along the unsheltered part 

 of the coast, at some places abundant but local. 



Ptilota plumosa (L.) Ag. 



Syn. Alg. p. 39, excl /?; Fucus plumosus L. Mant. p. 134. 

 Descr. Ptilota plumsa J. G-. Ag. Epicr. p. 75. 

 Fig. „ „ Harv. Pliyc. Brit. t. 80. 



Exsice. „ „ Aresch. Alg. Scand. exsicc. No. J 60. 



Syn. Fucus plumosus Gunn. Fl. Norv. 2, p. 91. 

 ., ptilotus Gunn. 1. c. p. 135. 

 „ cartilagineus Gunn. 1. c. p. 108; ex parte. 

 „ „ vindicatus Gunn. 1. c. p. 123; ex parte. 



„ plumosus a et £ "Wg. Fl. Lapp. p. 501 



A generally sublitoral alga, occurring on a depth of 

 2 — 16 fathoms. Sometimes it appears in rook pools within 

 the litoral zone attached to roots of Laminaria. Best devel- 

 oped and most abundant it is to be met with on stony or 

 rocky bottom on open coast, on a depth of 5 — 10 fathoms, 

 attached partly to the rock itself, partly to the stem of Maria 

 and Laminaria, especially L hyperborea. Particularly at 

 Berlevaag and Vardo I have collected very luxuriant speci- 

 mens, which had a length of 30- -35 cm. On some localities 

 it grows gregarious in rather large number. It appears also 

 in the greater bays or else in sheltered localities, but here it 

 never becomes so vigorously developed as on the unsheltere4 



