KONGL. 8V. VET. AKADEMIENS HANDLINGAK. BAND. 20. N:0 5. 235 



size from the other cells of the parenchyme of the lamina; (tab. 25, tig. 7). This seetns 

 to show that the L. saccharina which occurs on our coasts is not the same as the alga 

 of the same name whieh is found on the coast of France. With respect to my list of 

 synonyms, it may be remarked that it is founded in certain cases on mere suppositions. 

 It is impossible without having access to the original specimens to make out with cer- 

 tainty what the different authors have meant by their different Laminarioe. I hope 

 however to have in general hit upon the truth. If that is the case, L. saccharina in 

 its present limitation does not live within the Arctic Sea proper. 



Habitat. This species is sublitoral, growing in 2 — 10 fathoms water. As most 

 other Laminariacece , it prefers rocky bottom and is gregarious. It occurs on exposed 

 as well as sheltered coasts. In Musselbay on the north coast of Spitzbergen I found 

 during the winter both younger and older specimens, from such as were niicroscopical 

 in size to fully developed ones. Germinating plants were particularly numerous during 

 December. On the coast of Spitzbergen the present species bears ripe zoosporangia as 

 well during the winter, in November, December, January, February, and March, as 

 during the summer. However the formation of zoospores is at its richest in July and 

 August. Even on the west coast of Novaya Zemlya I have taken it with zoosporangia 

 in July and August. On the coasts of Spitzbergen the change of the lamina appears 

 to take place in May and June. 



Geogr. Distrib. This species is known with certainty only from the Spitzbergen 

 province of the Arctic region. In the Siberian province it is replaced by L. cuneifolia, 

 in the American by L. longicruris, and in the Atlantic by L. saccharina. It bas been 

 found most abundant and luxuriant on the coasts of Spitzbergen. Its northernmost 

 known locality is the North Cape of Spitzbergen Lat. N. 80° 31'. 



Localities: The Greenland Sea: the east coast of Greenland at Sabina Isle (?) ; the 

 coasts of Spitzbergen, common and abundant; Beeren Eiland. 



The Murman Sea: the west coast of Novaya Zemlya and Waygats, common and 

 abundant. 



The White Sea: probably plentiful. 



The Kära Sea: Uddebay on the east coast of Novaya Zemlya, Cape Palander and 

 Actinia Bay pretty plentiful, Cape Tscheljuskin scarce. 



Laminaria atrofulva J. G. Ag. 



Grönl. Lam. och Puc. p. 16. 

 Beser. Laminnria atrofulva J. G. Ag. 1. c. 



iSijn. Laminai-ia atrofulva J. G. Ag. Gröiil. Alg. p. 110. 



Addition to the description of the species. I consider this alga, which has been 

 described in detail by J. G. Agardh 1. c, to be one of the most characteristic Laminarioi 

 of the Arctic Sea. I have only to add to the author's description that this species, as 

 well as the next foUowing ones, has the raiddle layer of the lamina compact, sharply 

 defined from the intermediate layer. The latter layer is composed of angular or rounded- 



