- 143 — 



This species occurs on rocks and stones in the litoral region, often 

 in company with Hildenbrandia rosea and Verrucaria mucosa. It has 

 been collected with unilocular sporangia in February and May— July. 

 Specimens gathered in August — Sept. were sterile. 



E. I cel. Hölmanes, Eskifjöröur (Strömfeit). 

 N. I c el. Eyjafjöröur. 



NW. lcel. Kolbeinsâ, ßroddanes; IsafjÖröur (CO.); Bi'ldudalur. 

 SW. Icel. Reykjavik. 



Ralfsia verrucosa (Aresch.) J. Ag., Rke. Atlas Tab. 5 and 6, f. 1—13. 



I have found it growing on rocks and on other algæ e. g. Scyto- 

 siphon lomentarius and Chætomorpha Melagonium, in the litoral region. 

 It is only known from few places. Specimens with unilocular sporangia 

 have been gathered in June and September. 



E. Icel. Hölmanes, Brimnes. 

 N. Icel. Arnarnes. 

 NW. Icel. Kolbeinsâ, Skâlholtsvi'k. 

 SW. Icel. Reykjavik (G. 0.). 



Ralfsia deusta (Ag.) J. Ag., Rosen v. Grl. Havalg. p. 898. 



This species I have only met with in the litoral region and especially 

 in pools below half-tide level, the bottom of which often is totally covered 

 by the widely expanded crusts. All my specimens, gathered in May — Sept., 

 are sterile. 



E. Icel. Djüpivogur, Hölmanes, Brimnes, Borgarnes. 



N. Icel. Arnarnes. 



NW. Icel. Kolbeinsâ. 



SW. Icel. Stykkishölmur, Reykjavik. 



S. Icel. Vestmannaeyjar. 



Myrionema vulgare Thuret, Sauvageau Myrionema p. 185. 



I have now and then met with plants having a basal disc with 

 marginal growth, branched assimilative filaments, basal hairs enclosed in 

 a sheath below, and about 6 disc-shaped chromatophores in each cell. 

 The specimens agree well with the description of Myrionema vulgare, 

 and I refer them to this species, although they are all sterile. 



N. Icel. Höföi. 



SW. Icel. Reykjavik. 



Myrionema Corunnæ Sauvag. Myrionema p. 237. 



I have in one place in S. Iceland met with specimens growing on 

 the sorus of Laminaria hyperborea, which fully agree with Sauvageau's 

 exhaustive description (1. c). The margin of the basal disc of my spe- 

 cimens is usually like Sauvageau's Fig. 14, A (I.e.), but occasionally I 



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