56 



H. JONSSON 



Table 2. The Distribution of the 76 species not common to all 

 the coastal districts (continued). 



1 7. 1 so 



B 



18. Ceratocolax Hartzii 



19. Polysiphonia arctica .... 



20. Ptilota pectinata 



21. Peyssonellia Rosenvingii. 



22. Coilodesme bulligera 



23. Cruoria arctica 



Total . . . 



15 



13 



+ + + 

 (+)(+) + 



(+) 



1 



13 



43. Ceramium arborescens 



44. Ahnfeltia plicata 



45. Cystoclonium purpura- 

 scens 



46. Ptilota plumosa 



47. Petrocelis Hennedyi 



48. Corallina officinalis 



49. Lithophyllum Crouani 



50. Polysiphonia nigrescens 



51. Myrionema vulgare 



52. Leathesia difformis 



53. Delesseria sanguinea 



Total 



To illustrate more distinctly how the species with a north- 

 eastern distribution (A) and those with a south-western distribution 

 (B) intermingle in N., NW. and SW. Iceland I subjoin the following 

 figures taken from the preceding table: — 



A 



i. I eel. 



N. Icel. 



NW. Icel. 



SW. Icel. 



S. Icel 



(1) 



10 



13 



40 



40 



15 



9 + 4 



8 



5 



. . 



Notes on the species. Of the 4 species (A, 1 — 4, Tab. 2) 

 which have been found only in E. Iceland, Nos. 1 and 3 occurred 

 in great abundance in several of the fjords, while Omphalophyllum 

 was found only in Rey5arfj6r5ur, where it occurred abundantly, 

 and Acrosiphonia in one place only. Delesseria Baerii, I suppose 

 (31, p. 140), has originated from either E. or N. Iceland. 



Turnerella is most common in E. Iceland, and in addition to 

 the habitat in N. Iceland which has been published (31, p. 135) has 

 been found by B. Ssemundsson in Steingrfmsfjoruur in the most 

 western part of the north coast; consequently it must have a wide 

 distribution along this coast. With regard to Lithothamnion foecun- 

 dum and Laminaria fceroensis it must be assumed that they are 

 more frequent in E. and N. Iceland than is known at present, and 

 as the latter species occurs in the Faeroes, it may well be expected 

 to be met with on other parts of the coast of Iceland. 



