KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 20. N:0 5. 109 
f. tenuissima Rupr. (nob.) 
Fuscaria tenuissima Rupr. Alg. Och. p. 221. 
@. prolifera nob. 
f. fronde prioris anni a ramis persistentibus prolifera. 
Descr. Fuscaria tenuissima Rupr. |. ec. 
Fig. » » » tab. 10. 
2. glacialis nob. 
Descr. Khodomela tenuissima KJsPLuM. Spetsb. Thall. 1, p. 6. 
Fig. » » » » » tab. 4, fig. 1—2. 
Exsice. » » » in Arescu. Alg. Scand. exsice. N:o 402. 
Syn. Aphanarthron cladostephus J. G. AG. Spetsb. Alg. Bidr. p. 9. 
Fucus lycopodioides Gunn. Fl. Norv. 2, p. 80. 
» » Wg. Fl. Lapp. p. 505. 
» — subfuscus » >» » » »  Cfr, Argescu. Obs. Phyc. 3, p. 7. 
Fuscaria tenuissima Rupr. Alg. Och. p. 221. 
Rhodomela cladostephus J. G. AG. Spetsb. Alg. Till. p. 48. 
» lycopodioides J. G. Ac. Gronl. Alg. p. 111. 
» » Arescu. Phyc. Seand. p. 262. 
» » KseLim. Spetsb. Thall. 1, p. 8; Algenv. Murm. Meer. p. 10 
» » KLEEN, Nordl. Alg. p- 12. 
» » Nyl. et Sel. Herb. Fenn. p. 74. 
» subfusca (var?) J. G. Ac. Spetsb. Alg. Progr. p. 3; Bidr. p. 11. 
» » Dickie, Alg. Cumberl. p. 238. 
» » Gost, Algenfl. Weiss. Meer. p. 24. 
» » KseLLM. Spetsb. Thall. 1, p. 5. 
» » KEEN, Nordl. Alg. p. 12. 
» » Post. et Rupr. Il: Alg. p. I. 
» tenuissima KseLim. Vinteralg. p. 64; Spetsb. Thall. 1, p- 6; Algenv. Murm. Meer. p. 
10 et Kariska hafvets Algv. p. 19. 
Remark on the species. Gost, in his account of the Flora of the White Sea, has 
defended the opinion entertained also by other algologists, that Rhodonwla lycopodivoides 
is not specifically distinct from Rh. subfusea (Woopw.) Ac. In support of this opinion 
he alleges, firstly that these two forms of Rhodomela, taken for different species, agree 
perfectly in anatomical structure and differ only by outward characteristics, amongst 
which is a somewhat different variety of colour, secondly that there are to be found 
transitions between them, as has been pointed out already by Harvey, and lastly that Rh. 
subfusca, whose distribution is more southerly, changes gradually in habit as it advances 
towards the north, passing into that Rh. lycopodioides which is characteristic of higher 
latitudes. Amongst the transitional forms that Rhodomela ought to be numbered 
according to Gopi, which has been named Fuscaria tenuissima by Ruprecur and whose 
claim to be regarded as a separate species I have tried before to justify. 
I cannot but accede to this view so far on the one side, as to allow the claim 
of Rh. tenuissima to be considered as a separate species to fall. My observations and 
studies of its forms as occurring in the south-eastern part of the Siberian Sea, compel 
