58 KJELLMAN, THE ALGH OF THE ARCTIC SEA. 
northern Atlantic and the northern Pacific may have stayed there from those times 
when northern Europe was surrounded with a sea filled with ice stretching down to the 
present northern coast of France. It is not at all improbable that the Flora of this sea 
may have been similar to that of the present Arctic Sea. When the glacial formation 
diminished in the south, southern plants immigrated in the sea as well as on the land, 
dislodging the. main mass of the glacial ones. However, some of these, being able to hold 
out the struggle against the new-comers, maintained themselves in their original home 
and have done so ever since. Even though, as I have tried to show above, the present 
poverty in alge in the eastern part of the Kara Sea and in the Siberian Sea may depend 
essentially on the unfavourable nature of the bottom and the slight salinity of the water, 
still it is probable that during the oldest glacial period, when these seas extended 
farther southwards than now, the configuration of the coast and the condition of the 
water were more advantageous for alge and that the marine vegetation of these parts 
of the Arctic Sea was not then so poor’). The occurrence of several species, as De- 
lesseria Bari, Rhodophyllis dichotoma, Petrocelis Middendorffi, Ptilota pectinata a. 0., in 
the Ochotsh Sea, the Murman Sea and the Spitzbergen Sea, and their absence in the 
intermediate region of the arctic waters, may be explained by the hypothesis that these 
species formerly grew also in the last-mentioned sea-region, but succumbed afterwards, 
because the shore was moved northwards, partly through the formation of deltas, partly 
through a general rising of the land elevating the sea-bottom, which was formed of 
sand-banks, and because large rivers began to pour ever increasing masses of fresh 
water into the sea. If Halosaccion saccatum, reported from the White Sea, is really 
to be found there, it should probably be numbered among those species which have 
formerly been more widely spread along the coast of Siberia; for, even though it be 
not identical with any of the species of the Pacific, H. fucicola, H. hydrophora, or H. 
jfirmum, these are nevertheless its nearest relations. The change suffered by the Flora 
in the northern Atlantic and the northern part of the Pacific, in proportion as the 
glacial formation retreated, took place even in the part of the Arctic Sea surrounding 
the coast of Norway. By the immigration of southern forms, glacial species were su- 
perseded or deprived of their predominating influence. The elements of the Flora were 
considerably increased, and its character was no longer marked by glacial forms, but 
by such as belong to the Atlantic. However it is not only into this part of the Polar 
Sea, most closely allied hydrographically to the present northern Atlantic, that southern 
species have probably immigrated in later times, or are now in course of immigration; 
but this is the case also with the Arctic Sea proper. Such a transplantation of alge 
into certain parts of the Arctic Sea is very much favoured by currents flowing in that 
direction. Thus, for instance, alge may be easily transported into the eastern part of 
the Greenland Sea to the coast of Spitzbergen by the Gulf Stream, and into the eastern 
part of the Murman Sea to the west coast of Novaya Zemlya partly by means of this 
stream, partly along the almost continuous coast from the Norwegian Polar Sea and 
the western Murman Sea. Between Spitzbergen and Norway at different latitudes I 
') NoRDENSKIOLD, Préven, p. 70—71. 
