Simmons, Remarks about the Relatious of the Floras etc. 
181 
mentioned families, but in the light of our present knowledge 
I think it can hardly be regarded otherwise. 
An inspection of the tableYIII further corroborates theopinion 
already pronounced, that there is a very near affinity between 
the floras of the Arctic Sea and the northern Atlantic, so close 
indeed, that it seems dubious, if not the marine floras of most parts of 
the arctic regions are to be looked upon as merely provinces of the 
atlantic flora, nothwithstanding the great differences that must 
have prevailed between the preglacial vegetations among whom 
their ancestors are to be sought. It is pointed out previously that 
the number of species that can without restrictions, be regarded 
as endemic in the arctic regions is all but considerable, and 
that only few species are distributed all over the arctic area. 
If the present arctic flora was the result of a long unbroken 
development within the area it now occupies, there would in 
all probability exist a number of endemic genera, and these as 
well as a greater number of endemic species must also be spread 
over great parts of the area. Now only one endemic, monotypic 
genus exists, that has a very narrow limit, as far as hitherto 
known, and the endemic species mostly have a distribution only 
within a small area. Most of them moreover pertain to genera, 
where there has been doubtless of late a lively production of 
new forms, or where probably such generation is still in progress, 
as is shown by the many closelv allied or hardly distinguished 
species of such genera as Laminaria , Maria, Rliodochorton, 
described from the arctic regions. Such a fact does not speak 
against the assumption, that the arctic marine flora has immi- 
grated in postglacial time, likewise as the atlantic flora, f. i. at 
the norwegian coast, and the landfloras of the former glaciated 
areas in general, as is shown by the existence in those areas of 
such genera as Hieracium, Taraxacum and perhaps others, 
including many local species. 
Kjellman speaks of the great number of monotypic genera 
as proving the considerable age of the arctic flora. Now the 
number of genera is 80 (43 of Phaeophyceae, 37 of Rhodo- 
phyceae), all with a single exception also present in the Atlantic. 
Among them are 15 (19) monotypic ones, which indeed is a 
great number, but except Coelocladia , as formerly mentioned, thev 
are all also atlantic, and most of them have them principal 
distribution south of the Arctic Sea. Some, f. i. Pelvetia, Du- 
montia, Furcellaria, Rolyides , beyond doubt are to be reckoned as 
tertiary-atlantic, consequently I cannot in their existence see 
any cause for the supposition of a long development within the 
Polar Sea. Of the 42 genera of brown algae ( Coelocladia ex- 
cepted) 16 are atlantic-arctic, 14 atlantic-arctic-pacihc, 12 have 
a wider distribution. Of the 37 genera of Rhodophyceae 7 are 
atlantic-arctic, 12 atlantic-arctic-pacific, 18 have a wider ränge. 
Consequently even here the affinity between the atlantic and 
the arctic flora is expressed, the atlantic genera of the arctic 
flora beeing 99 in a hundred, the pacific ones only 66. 
