170 
Simmons, Remarks about tlie Relations of the Rloras etc. 
liand, if tlie extremely arctic, wide spread L. solidungida 
does not grow in the Pacific, as seems most probable after the 
betöre mentioned Statement of Setchell, we should there have 
a true arctic species, that would give a certain support to the 
theory of Kj eil man, as it is among the algae who can perhaps 
with a better right than most others be set up as survivors of 
the glacial period in the Polar Sea itself. 
All the 6 Rliodoyhyceae must be said to be little known and 
pertaining to genera, as yet too insufficiently studied, to be apt 
to be used to prove anything about the history of tlie arctic 
Hora. Moreover one, Rhodochorton intermedium , is said to be 
identic with Rh. Rothii (Jönsson, 28, p. 2). I think already 
what is hitherto said, will be almost enougli to prove that we 
can not have any right to conclude from tlie endemism in the 
Polar Sea, that there lias been a long-continued evolution of 
species, having their original liomestead in those ice-encumbered 
waters, and never having quitted them even during the most 
unfavorable times of the iceage. 
The great number of species (64, 40 per ct.) common to 
the nortli Atlantic, the Polar Sea and the northern Pacific could 
certainly also seem to support the above mentioned view of 
Kjellman, but, if this cifcumstance is examined together with 
another, I think it will sooner prove quite a different course of 
development. I mean tlie fact that a number of species, not 
growing in tlie Polar Sea, are notwitlistanding found in the 
northern parts as well of the Atlantic as of the Pacific. 
J. G-. Agardh has been the first algologist to draw the 
attention to tlie qnestion about tlie appearance in widely 
different parts of the world of tlie saine species. When he 
first commented npon it in 1862 (2) he was most inclined to 
think, that botanists, who profess to have found common 
european species in far away seas, have been missled by sonie 
outward likeness; corresponding but not identic species liave 
been found. Where still the same species occur in different 
regions, the distribution is due to the currents; thus he speaks 
of an american-european floral province within the ränge 
of the colder part of the Gulfstream, and of a circum- 
american province that is chäracterized by Agarum and by 
other Laminaria- species than the former. Even the latter 
should have got its limits through currents. This view is again 
discussed and upheld in another paper (4, p. 8—9 and 11) 1872, 
but in the mean time Agardh has himself identified an alga 
from Spitzbergen with a species described from California 
(Fucus Harveyanus) in a treatise publislied 1868 (3, p. 10) and 
here he also speaks of tlie joint appearance of many. species of 
algae in the Atlantic and Pacific. He tliinks that this is due 
to a current that transports algae from New Eoundland and 
Spitzbergen to north Western America and Kamshatka, But as 
Kjellman (30, p. 55) points out, such a current is never ob- 
