— 134 — 



this variety; but as it is different by distinct characters, being generally 

 larger, the vertical filaments considerably thicker below than above, and 

 the ramification first beginning at a considerable distance from the base, 

 I have taken it as a new species. 



I have seen specimens of G. Alariæ from Haugesund (Norway) 

 collected by L. K. Rosenvinge the 6. Aug. 1885, growing on the lamina 

 of Alaria esculenta, resting undetermined in the Bot. Mus. in Copenhagen. 

 The Norwegian plants agree very well with the Icelandic specimens. 

 The filaments are below 16//, above 8 // thick; the sporangia 14 — 17 /* 

 long and 10 — 11// broad. 



In the Phycotheca boreali-americana Nr. 236 the same species also 

 occurs (sub nom. G. secundata (Lyngb.) Thür.), growing on the lamina 

 of Alaria esculenta, collected in July 1894 by F. S. Collins in Hardhead 

 Island, Penobscot Ray, Maine. The American specimens agree very well 

 with the Icelandic-Norwegian plants. The filaments are below 16//, above 

 8// thick; the sporangia 20 fj. long and 14// broad. 



The same species has also been collected (1895) in the Færoe Isles 

 by F. Börgesen, growing on Alaria esculenta. 



SW. I c el. The Maelstrom in Hvammsfjöröur — Gathered in June. 



Fam. Gigartinaceæ. 

 Chondrus crispus (L.) Stackh., Strömf. Algveg. p. 31. 



It grows in the litoral region and is very common on rocks and in 

 rock-pools at low-water-mark. Collected with tetrasporangia in May and 

 with cystocarps in May-July. 



The thallus of this species is varying in breadth and ramification 

 and thus there occur three forms : 



F. typica (fig. Kiitz. Tab. phyc. Vol. 17, Tab. 49 a) is the most common 

 form, 9 — 11 cm. high; the upper branches 2 — 5 mm. broad. 



F. latifrons Le Jolis: Algues marines de Cherbourg Nr. 164 (fig. 

 Harv. Phyc. Brit. Tab. 63 f. 2) with few and broad branches, 8 — 10 cm. 

 high; the upper branches 5 — 10 mm. broad. In S. and SW. Icel. 



F. angustifrons Le Jolis: Algues marines de Cherbourg Nr. 224. 

 (fig. Harv. Phyc. Brit. Tab. 63 f. 1) richly branched, 15 cm. high; the 

 upper branches 2—3 mm. broad. 



These three forms are connected with numerous intermediate forms 

 and both the broad and the small forms are not always with certainty 

 to be distinguished from the f. typica. 



NW. Icel. Cast ashore at Isafjöröur (Strömfeit). 

 SW. Icel. and S. Icel. common. 



