— 373 - 



the apical cell, the walls of which often enclose the rhizine as a sheath 

 (fig. 17 e). My specimens, gathered in May, were all sterile. This species, 

 I think, comes nearest to A. setacea Kjellm. (Acrosiphonia p. 69, Tab. II), 

 but differs from it by larger heigth and the shape of the apical cell (fig. 

 Ma), I have also in my plants never seen the apices of the rhizines form 

 a parenchymatous disc. In some respects my plants resemble Gladophora 

 sacculifera Kütz. (Tab. Phyc. Ill, Taf. 81, f. I) in other respects they remind 

 of A. hystrix. 



S. I cel. Vestmannaeyjar. 



Acrosiphonia penicilliformis (Fosl.) Kjellm., Acrosiphonia p. 80. 

 forma. 



I have in one place in E. Iceland met with some plants, which I 

 refer to this species. They are 4 cm. high and their main branches up 

 to. 1 70 ^ thick. The sporangia are frequently terminal, occurring singly 

 or 2— 5 in a continuous row, but intercalary sporangia also frequently 

 occur in the branches. In no other species of Acrosiphonia I have seen 

 terminal sporangia, and Kjellman mentions only one species, A. penicilli- 

 formis, having terminal sporangia, „ad complures seriatæ". My plants 

 agree for the most part very well with Kjellman's description, but are 

 differing by having the sporangia occurring singly or only 2 — 5 in a 

 row, I therefore call my plant A. penicilliformis (Fosl.) Kjellm. f. 



Fructiferous specimens have been gathered in June. My plants occurred 

 in pools in the upper litoral region. 



E. I cel. Brimnes. 



€ladophora rupestris (L.) Kütz., Rosenv. Grl. Havalg. p. 909 ; Strömf. 

 Algveg. p. 55. 



The Icelandic specimens are 4 — 15 cm. high and occur in the litoral 

 region, especially in its middle part. It is undoubtedly common along the 

 coasts of S. and SW. Iceland. 



NW. Ice). Broddanes; Aöalvfk (Ldbk.). 

 SW. I cel. Stykkishölmur; Reykjavik (CO.). 

 S. I cel. Eyrarbakki (Strömfeit). 



Cladophora hirta 1 ) Kütz. Kjellm. in Wittr. et Nordst. Exsicc. Nr. 1041. 

 I have with some doubt referred to this species some specimens 

 collected by Strömfeit at Eyrarbakki in the litoral region. Strömfelt's plants 



l ) As the Cladophora-species at present are very unsufficiently known I think 

 it more correct to distinguish too much than too little. My determining 

 of this and the following species of Gladophora must be regarded as pro- 

 visional. 



