I. LIST OF THE MARINE ALG.E. 



THE following List of the Marine Algae of Iceland is extracted 

 from my earlier publications (Jonsson, 31, Borgesen and 

 Jonsson, 14) and from the paper by Henning Petersen (57) 

 on the species of Ceramium. It gives only the names of the species 

 with synonyms, their distribution in the different coastal districts 

 and some new habitats. The limitation of species is unchanged 

 except in the case of the genus Ceramium and in Clathromorphum 

 circumscriptum (Stromf.) which is included in Clathromorphum com- 

 pactum (Kjellm.) as proposed by Foslie. One species, Vaucheria 

 sphcerospora Nordst. (Borgesen and Jonsson, 14), is omitted from 

 the list as it can scarcely be called a Marine Alga. Of Ceramium 

 5 species are added. 



Thus the number of species is: 



76 Rhodophycese 

 67 Phaeophyceae 

 51 Chlorophycese 

 6 Cyanophyceae 



Total. . . 200 species. 



The coastal districts are the following (see the map, p. 7):- 

 East Iceland (E. Icel.), from L6nshei5i (Eystra horn) to Langanes. 

 North Iceland (N. Icel.), from Langanes to Hornbjarg (Kap Nord). 

 Northwest Iceland (NW. Icel.), from Hornbjarg to Latrabjarg. 

 Southwest Iceland (SW. Icel.), Brei5ifjor5ur and Faxafloi from Latra- 

 bjarg to Reykjanes. 



South Iceland (S. Icel.) from Reykjanes to Vestmannaeyjar and east- 

 wards to L6nshei5i (Eystra horn). 



In "The Marine Algae of Iceland" (Jonsson, 31) the district NW. 

 Icel. is larger; it reaches from the inner end of Hiinafloi to Latra- 

 bjarg instead of as now from Hornbjarg to Latrabjarg. Localities 

 from the part of the coast which stretches from Hiinafloi to Horn- 



