XVII 



c. THE BOREAL-ARCTIC GROUP. 



The species of this group are common in the Arctic Sea and 

 the Boreal area of Ihe Atlantic at least as far south as to the At- 

 lantic coast of North Africa, probably some of them have a far 

 greater southern distribution. The species marked with an * might 

 possibly be considered as cosmopolitan. 



Rhodopbijceæ. 

 Baiigia fuscopurpurea (Dillw.) Lyngb. 

 Porphyra umbilicalis (L.) J. Ag. 

 Chantransia microscopica (Nag.) Fosl. 

 Ch. secundata (Lyngb.) Thur. 

 Ahnfeltia plicata (Huds.) Fries (not in 



Greenland). 

 Polysipbonia elongata (Huds.) Harv. (not 



common in the Arctic Sea). 

 * Antithamnion Plumula (Ellis) Thur. 

 Ceramium rubrum (Huds.) Ag. 

 Rhodochorton membranaceum Magn. 



R. Rothii (Turt.) Niig. 

 Hildenbrandia rosea Kutz. 



11 species. 



Phæopbyceæ. 

 *Ectocarpus littoralis (L.) Lyngb. 

 E. confervoides (Roth) Le Jol. 

 *E. siliculosus (Dillw.) Lyngb. 

 *Sc3'tosiphon lomentarius (Lyngb.) J.Ag. 

 *Phyllitis fascia (Mull.) Kutz. 

 *Fucus vesiculosus L. 

 Ascophj'llum nodosum (L.) Le .Jol. 



7 species. 



D. THE COLD-BOREAL GROUP. 



The species of this group have their area of distribution from 

 West France-England northward to South Iceland, the Færoes and 

 Nordland-Finmark. Some few species have occasionally been found 

 in the Arctic Sea, especially in the White Sea and the Murman 

 Sea and some few reach as far south as to the Mediterranean or 

 North Africa. 



Rhodophijceæ. 

 Erj'throtrichia ceramicola (Lyngb.)Aresch. 

 Porphjra coccinea J. Ag. 

 Chantransia Alariæ .Jonss. 

 Ch. Daviesii (Dillw.) Thur. 

 Choreocolax Poljsiphoniæ Reinsch. 

 Gigartina mamillosa (G. et W.) J. Ag. 

 Phyllophora membranifolia (G. et W.) 



J. Ag. 

 Callocolax neglectus Schmitz. 

 Sterrocolax decipiens Schmitz. 

 Cystoclonium purpurascens (Huds.) Kiitz. 

 Lomentaria rosea (Harv.) Thur. 

 Delesseria alata (Huds.) Lam. 

 D. sangvinea (L.) Lam. 

 Poh'siphonia urceolata (Lightf.) Grev. 

 P. violacea (Roth) Grev. 



Botany of the F:eroes. Appendix. 



P. fastigiata (Roth) Grev. 



P. atrorubescens (Dillw.) Grev. 



P. nigrescens (Huds.) Harv. 



Rhodomela subfusca (Woodw.) Ag. 



Spermothamnion Turneri (Mert.) Aresch. 



Callithamnion polyspermum (Bonnem.) 



Ag. 

 C. Hookeri (Dillw.) Ag. 

 C Arbuscula (Dillw.) Lyngb. 

 C. roseum (Roth) Harv. 

 Plumaria elegans (Bonnem.) Schmitz. 

 Antithamnion floccosum (Mull.) Kleen. 

 Ceramium Deslongchampsii Chauv. 

 C. circinatum (Kutz.) .1. Ag. 

 C. diaphanum (Lightf.) Roth. 

 C. acanthonotum Carm. 

 Rhodochorton seiriolanum Gibs. 



