54 KJELLMAN, THE ALG^ OF THE ARCTIC SEA. 



sibly have issued from D. Bcerii or from some parent form common to both. Besides, 

 there can be adduced no reason why the arctic algge might not be supposed to have 

 been more widely distributed formerly in the arctic regions than they are now, which 

 is assumed on very good reasons to be the case with the arctic phanerogams. 



What has been said now about Delesseria Bcerii, may be applied, though with 

 one or two modifications, even to the other above-mentioned species, that are met with 

 in the Arctic Sea and south of it only in the northern part of the Pacific. By means 

 of the table exhibiting the geographical distribution of the arctic algse and the more 

 detailed data set forth in the special part of this work, every one may easily convince 

 himself of this fact. It is neither necessary nor suitable to enter here into details with 

 regard to each species. But I will, however, call attention to one of them, Laminaria 

 solidungula, one of the most peculiar and characteristic algee of the Arctic Sea. It is 

 found in the Arctic Sea almost circumpolar: in the Greenland Sea, where it is com- 

 monly distributed along the whole west and north coasts of Spitzbergen, and not seldom 

 attains such a considerable size as to become one of the most magnificent algse of 

 the ocean, in the Murman Sea, the Kära Sea, the Siberian Sea not far from the mouth 

 of Behring Strait, and in Baffin Bay on the west coast of Greenland. It probably 

 groAvs also in the American Arctic Sea. South of the Arctic Sea it is knoAvn only 

 from one place, namely the Ochotsh Sea, from where Ruprecht reports a young »abnor- 

 mal specimen of Laminaria saccharina with undivided scutiform root», which is in all 

 probability a young Laminaria, solidungula ^). 



The present Flora in the northern part of the Pacific differs so essentially in 

 composition from that of the Northern Atlantic, that is to say, it contains many species 

 that are so sharply distinguished from those of the Atlantic, even belonging to quite 

 different types, that in order to account in any way for this fact, one is necessarily 

 obliged to assume that these two divisions of the ocean appertain to different areas ot 

 development, within which different forms have continued to be evolved during a very 

 long time. However, on the other hand, it is a well-known fact that the northern 

 Atlantic has no inconsiderable number of species in common with the northern Pacific. 

 Though it is highly probable, as J. G. Agardh has rightly remarked, that »a great 

 part of the statements about alga3 occurring in widely distant seas is attributable to 

 imperfect knowledge and wrong determinations caused thereby, and that the number 

 of such species as are supposed to grow in widely distant seas will be diminished in 

 proportion as the accuracy of the scientific determinations increases», and though this 

 general judgment may be true even with regard to the reported number of species 

 reputed common to the northern Atlantic and the northern Pacific, still there are un- 

 doubtedly to be found in these widely separated sea-regions, as the same algologist 

 expressly points out, several forms that can be proved to be identical ^). The present 

 hydrographical conditions being so essentially unlike, it can hardly be assumed that 

 these species should have been developed both in the northern Atlantic and in the 



') Cp. RupEECHT, Alg. Ocliot., p. 351 and J. G. Agardh, Lamin. p. 8 and Grönl. Lamin. och Fuc. p. 11. 

 ^) Cp. J. G. Agardh, Spetsb. Alg. Progr. p. 1. Spetsb. Alg. Bidr., p. 10. Grönl. Lamin. oeli Fuc. p. 8 — 

 9, 11, etc. 



