~ 358 — 



E, I eel. Bfimnes. 

 SW. Icel. Reykjavik. 



S. Icel. Eyrarbakki, Vestmannaeyjar. 



[Ilothrix flacca (Dillw.) Thur., Rosenv. Grl. Havalg. p. 935. fig. 44; 

 Wille, Studien p. IS, Tab. I-II, fig. 54-63. 



The Icelandic specimens agree well with the description and figures 

 given by Rosenvinge (1. c.) and Wille (1. c). The plant attains a length 

 of 1,5 cm., the sterile filaments are 14 — 40/^ thick and the fructiferous 

 filaments up to 87 ^i thick. It has usually 2 — 3 pyrenoids in each cell 

 sometimes only 1 pyrenoid and occasionally 4. Fructiferous specimens 

 have been gathered in March — August. The species is exceedingly common 

 along the coasts of Iceland and occurs gregariously on rocks at high- 

 water mark, often in company with Urospora mirabilis and Monostroma 

 groenlandicum. Not rarely it has also been found on Fucaceas and 

 Rhodymenia palmata in the litoral region and on Laminaria in the upper- 

 most part of the sublitoral region in a depth of about 1—2 fathoms. 



Fam. Cheetophoraceae. 



Pseiidendoclouiuin subniariniiin Wille, Studien p. 29. Tab. III. fig. 101 

 -134. 



To this species I have referred some specimens I met with in 

 E. Iceland, covering wood-work at or above high-water mark with a 

 matted growth. As pointed out by Wille it penetrates the wood- work, 

 and transverse sections of the wood show the tracheids more or less filled 

 up with its filaments. 



E. Icel. Djupivogur. 



Entoderina Wittrockii (Wille) Lagerh., Rosenv. Grl. Havalg. p. 934. 



I have met with this species in the outer cell-walls of Elachista 



fucicola and Pylaiella littoralis. Collected with spores in May in S. Iceland. 



N. Icel. EyjafjorDur. 



NW. Icel. Prestsbakki, Kolbeinsa. 



SW. Icel. Stykkisholmur, Einarslon, Reykjavik. 



S. Icel. Vestmannaeyjar. 



Acrochsete parasitica Oltm. Hot. Zeit. 1894, p. 208; Rosenv. Deux. 

 Mem. p. 114. 



I have only met with some few sterile specimens (gathered in March) 

 growing in Fucus inflatus in company with Ulvella fucicola. Probably it 

 will turn out to be more common. 



SW. Icel. Reykjavik. 



