13 



and long branches. Besides, from the lower part of the hypothallus 

 at first apparently crustlike and pretty strongly developed in a later 

 stage of development coarse and ocsasionally decumbent branches 

 issue, so that the hypothallus by and by forms a subcentral main 

 axis, which never appears to be due to L. glaciate. 



Habitat. The species apparently lives in the lowest part of 

 the sublitoral region, or in the elitoral one. It is said to have been 

 picked up by fishermen from a depth of 20 — 30 fathom. 



Occurrence. Hitherto with certainty only found at Gjesvasr 

 in the neighbourhood of the North Cape, a solitary specimen. 



Lithothamnion glaciale Kjellm. 



N. Ish. Algfl. p. 123 (93). 



f. typica Fosl. mscr. 



f. ramis conicis, obtusis vel subcylindricis, usque 7 — 8 mm. 

 altis, inferne diametro usque 5 mm. 

 Fig. Lithothamnion glaciale Kjellm. 1. c. t. 2 — 3. 



f. torosa Fosl. mscr. 



f. crusta tuberculis subhemisphsericis, 0.5 — 1 cm. magnis in- 

 structa. Tab. nostr. 1. 



Syn. Lithothamnion calcareum Kjellm. Vinteralg. p. 64. 



„ „ Kleen, Nordl. Alg. p. 1 1 ; sec. Kjellm. 



„ fasciculatum Aresch. Obs. Phyc. 3, p. 5 (ex parte) ; sec. 



Kjellm. 

 „ „ Gobi, Algenfl. Weiss. Meer. p. 22. 



„ „ Kjellm. Spetsb. Thall. 1, p. 3, Algenv. Murm. 



Meer. p. 7. 

 „ glaciale Fosl. Contrib. I, p. 7. 



„ „ Stromf. Algveg. Isl. p. 18. 



„ „ Rosenv. Gronl. Havalg. p. 773. 



Remark on the species and the definition of the form. The 

 most extreme forms of this species are rather differing. It probably 

 includes more than the above quoted ones, but they are on the 

 other hand not well defined, as transitions frequently are to be 

 found. The form figured by Kjellm an 1. c. I consider to be the 

 typical one, characterized by its mostly numerous conical branches 

 in the crust as well as the lobes. Smaller specimens of this form 



