Simmons, Remarks about the Relations of the Floras etc. 
173 
A few (7) species in the list are markecl with *; these are 
such as have also a more Southern distribution, either in the 
warmer seas or äs well in the Southern as in the northern tem- 
perate zone. For them the possibility of a Southern way of 
immigration must be admitted, perhaps also their origin dates 
far back in the tertiary period. Still of the 16 Phaeophyceae 
and 22 Rhodophyceae in the table 31 species have a distribution 
that can hardly be accounted for otherwise than through assu- 
ming their original home to have been in the present arctic 
regions. 
Indeed it is no great number compared to the total of the 
atlantic or pacific flora, but then we also must remember the 64 
atlantic-arctic-paeific species from table VI. Thus a number of 
about 100 algae, common to the northern parts of the oceans 
on both sides of America is reached, at all events a rather con- 
siderable part of the total figures. Moreover the numbers in 
table VII could with a good right be increased by transferring 
from table VI such species as are found in the Arctic Sea only in 
a limited region immediately beyond the northern border of the At- 
lantic as here defined. Among these are: Polysiphonia nigres- 
cens , Dumontia filiformis, Corallina officinalis from the Murman 
or White Seas; Maria esculenta from Spitzbergen and further 
some species, found either in Western Greenland alone or besides 
also at the european nortlicoast, but not in other arctic districts. 
Even about these it holds true, that if they have now for the 
first time entered the Polar Sea, it becomes impossible to give 
any reason for their appearance also in the Pacific. On the 
other hand if we think species with such a distribution to be 
what I will call tertiary-polar species, i. e. such as have had their 
former home in the sea around the pole, it becomes natural, 
that they should have been driven soutliwards by the glaeiation 
both into the Atlantic and the Pacific and there have got their 
present distribution. 
We now must go back to what we know about the terti- 
ary flora of the polar regions, and to the conclusions that can 
be drawn from that knowledge. In the miocene time there has 
been a rather warm climate far up in the present arctic re- 
gions, as is shown by the plantfossils found not only about 70 o 
on both coasts of Greenland but also to the north of the 80 th 
parallel in Grinnelland. If at all there existed tlien a flora that 
could be called arctic, it must have had a very limited area. 
For the present research it can liowever be left out of conside- 
ration if there already so long ago were any algae that lived 
under arctic conditions or if the arctic species were formed 
first during the preglacial period, that is wlien the deterioration 
of climate began. Species that were not able to adapt themsel- 
ves to the gradually less and less favorable conditions of life, 
must then either have been exstirpated or driven soutliwards 
