— 191 — 



F. inflatus F. distichus L. is identical, the name F. distichus ought not to be 

 used at all, but, if used, 1 think, it might rather replace the name f. linearis, 

 as it is used by older writers, than be given to this dwarf form. 



The more typical Icelandic specimens, I have referred to this form, 

 are 5—9 cm. high. The frond is 2 — 4 mm. broad, thick and leathery, 

 never inflated and below comparatively very thick and almost terete. The 

 midrib is usually indistinct above. The receptacles are 0,5—3 cm. long 

 and 2 — 4 mm. broad, undivided or bifide. As I have said before, this 

 form is connected to the main form by several intermediate forms (cfr. 

 also Börgesen 1. c). 



It occurs on sloping rocks at or above high-water mark in the most 

 exposed situations. 



The main-form and f. linearis are exceedingly common, and f. eva- 

 nescens is found here and there. Typical specimens of f. exposita have 

 only been gathered in SW. Icel. at Öndveröarnes and in S. Icel. at Melvik 

 (G. 0.), but I suspect it will turn out to be much more common. 



Fucus inflatus goes higher up and longer down than other Fucaceæ 

 along the coasts of Iceland, as it is found from above high-water mark 

 to a little below low-water mark. It is consequently open [to highly varying 

 environmental influences to which I think the variations of this species 

 are due. The most determining factors I see in the more or less move- 

 ments of the water, as the species essentially is varying in regard to size 

 and consistence of the frond. The main form, which grows gregariously 

 at half-tide level on somewhat exposed coasts, I take as a normal type 

 for the species. 



Fucus serratus L., Kjellm. Arct. Alg. p. 198. 



The Icelandic specimens are well agreeing with f. typica (Kjellm. 1. c.) 

 and the fig. in Harv. Phyc. Brit. Tab. 47. I have only found this species 

 in two places: at Vestmannaeyjar, where it occurred rarely in the lower 

 litoral region, while in Hafnarfjöröur it grew gregariously in the Fucus-zone 

 on the southern side of the fjord. 



Fructiferous specimens have been gathered in May and September. 



SW. Icel. Hafnarfjöröur. 

 S. Icel. Vestmannaeyjar. 



Fucus vesiculosus L., Kjellm. Arct. Alg. p. 198, Strömf. Algveg. p. 34. 



In company with Ascophyllum nodosum and Fucus inflatus it forms 

 the Fucus-zone at half-tide level and especially its upper part. It grows 

 more abundantly in the interior of fjords, whereas F. inflatus is more 

 gregarious in the exterior of fjords. F. vesiculosus grows, as the other 



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