134 KJELLMAN, THE ALG^ OF THE ARCTIC SEA. 



Delesseria angustissima (Turn.) Griff. 



ill Harv. Phyc. Brit. t. 83. Fucus alatus y angustissimus Turn. Hist. Fuc. 3, p. 60. 

 Descr. Delesseria angustissima J. G. Ag. Spec. Alg. 2, p. 686. 

 Fig. » » Harv. Pliyc. Brit. 1. c. 



Syn. Delesseria alata var. angustissima Kleen, Nortll. Alg. p. 14. 



Remark on the determination of the species. I have never seen any specimens of 

 this alga from the Polar Sea collected by others, nor have I ever met with it there 

 myself. It is only on the authority of Kleen that I give it a place in the present 

 work. Kleen's. collections contain no specimens of this species, but in his list of the 

 alg£E of Nordlanden he declares decidedly that D. angustissima Harv. Phyc. Brit. pi. 

 83 was found there common. I have no reason to suppose that Kleen's statement 

 should not be founded on accurate comparisons, and the alga growing at Scotland and 

 the Orkney isles, its occurrence at Nordlanden is highly probable. 



Habitat. It is litoral, attached to stones beneath Fucaceoe. 



Geogr. Distrib. It is known only from the Atlantic region of the Polar Sea, in 

 the southern part of which region it is commonly spread, according to Kleen. 



Locality: the Norwegian Polar Sea: Nordlanden common and plentiful. 



Delesseria alata (Huds.) Lamour. 

 Ess. p. 124. Fucus alatus Huds. F1. Angl. p. 578. 

 Descr. Delesseria alata J. G. Ag. Epicr. p. 483. 

 Fig. » » Harv. Phyc. Brit. t. 247. 



Exsicc. » » Aresch. Alg. Scaud. exsicc. N:o 75. 



iSijii. Delesseria alata Aeesoh. Phyc. Scand. p. 292. 

 » » Kleen, Nordl. Alg. p. 14. 



Fucus alatus Gunn. F1. Noiv. 2, p. 91. 

 « » Wg. F1. Lapp. p. 492. 



Habitat. In the southern part of the Norwegian Polar Sea at Nordlanden this 

 species grows partly in rock-pools between tide-marks, partly within the upper part of 

 the sublitoral zone, attached to stones or more usually to Lam.inariacetb. Farther north- 

 wards on the coast of Finmarken it always keeps, according to my experience, in the 

 litoral region, forming in exposed localities, together with Ptilota elegans, a dense mat 

 on the steep, flat or somewhat hollow, outsides of stones or rocks covered by masses 

 of Ozothallia and other Fucaceee. Here it is dwarfed, seldom, if ever, reaching more 

 than 3 — 5 cm. in height by 1 — 2 mm. in width, while even at Nordlanden it becomes 

 over 8 cm. long and about 4 mm. broad. The specimens from Nordlanden found in 

 Kleen's collections are all sterile, nor does he mention in his treatise on the marine 

 Flora of Nordlanden that he has ever seen any specimen with any kind of propagative 

 organs. Myself found only sterile individuals at Finmarken. On the west coast of 

 Sweden the plant bears tetrasporangia during the winter months, December and January, 

 and Areschoug states it to be »mensibus Martii atque Aprilis in mari Bahusiensi fruc- 

 tilicans». Accordingly, the plant here develops its organs of propagation in winter and 

 spring. Probably it does so also farther to the north. 



