KONGL. SV. VET. AKADEMIENS HANDLINGAK, BAND 20. N:0 5. 159 



The White Sea: Cp. Gobi 1. c. p. 12 and 43. 



Baffin Bay: the west coast of Greenland at Neuherrnhut. 



At Xordlanden the species occurs in its typical form, at other places, as far as 

 I have been able to ascertain, in a finer and more slender form, which agrees with that 

 distributed by Areschoug 1. c. as F. fastigiata f. tenuior. 



Fam. GIGARTINACEiE (Kutz.) J. G. Ag. 



Epior. p. 173; Kutz. Phyc. gener. 389; char. mut. 



Gen. Oystoelonium Kutz. 



Phyc. gener. p. 404. 



Cystocloniura purpurascens (Huns.) Kutz. 

 1. c. Fucus purpurascens Hdds. FJ. Angl. p. 589. 



f. typica. 

 Descr. Cystocloniura purpurascens J. G. Ag. Epicr. p. 239. 

 Fig. Hypnea purpurascens Harv. Phyc. Brit. tab. 116. 



>■ Cystoclouium purpurascens KiJTZ. Tab. Phyc. 18, tab. 15. 



Exsicc. » » AuESCH. Alg. Scand. exsicc. N:o 76. 



f. dendroidea nob. 



f. pumila, 7 — 10 cm. alta, thalli axi primario crassiusculo, inferne subnudo, supra medium decomposito- 

 ramoso, ramis fasciculura densum, circumscriptione semicircularem vel sustriangularem formantibus. Polysipho- 

 niam elongatam var roicrodendron habitu revocat. In formam typicam aperte abiens. 

 Syn. Cystocloniura purpurascens Gobi, Algenfl. Weiss. Meer. p. 40. 

 » » Kleen, Nordl. Alg. p. 18. 



» ii Zeller, Zvveite d. Polarf. p. 85. 



Eucus confervoides Wg. PI. Lapp. p. 504. 

 Gigartina purpurascens Nyl. et Ssel. Herb. Fenn. p. 74. 

 Hypnea purpurascens Ceoall, El. Disc. p. 459. 

 Soliera chordalis Ashm. Alg. Hayes p. 64? Cfr. Earl. New Engl. Alg. p. 148. 



Habitat. I know nothing about the habitat of the present species within the 

 arctic region of the Polar Sea. In the Norwegian Polar Sea it is litoraJ. The typical 

 form lives usually within the lowest part of the litoral zone, attached to other algae 

 or to steep rocks. In the upper part of this zone it is found chiefly in deep rock- 

 pools between tide-marks. The form dendroidea I have met with only in the upper 

 part of the litoral zone. It assumes here its most peculiar appearance, when growing 

 on the walls of shallow rock-pools where Mytilus edidis lives in great numbers. The 

 species flourishes both on exposed coasts and in sheltered places. It has been found 

 with tetrasporangia at Nordlanden in summer, with sporocarps in August. 



Geogr. Distrib. This species occurs in both divisions of the Polar Sea, but it is 

 scarce in the arctic. It reaches its maximum of frequency in the southern part of the 



