186 
Simmons. bemarks about tbe belations of tbe Floras etc. 
Laminariideae, Lessoniideae and Alariideae. All are present in 
tlie nortliern Pacific, but tlie Lessoniideae are totallv Avanting 
' <- V,_’ 
in tlie Polar Sea and tlie nortliern Atlantic, Avbere vre onlv 
# m c 
liave tlie genera Chorda , PhyUana . Saccorluza not arctic. 
and Laminaria of tlie subtribe Laminarieae, Agarum of 
tbe subtribe Agareae , and Maria of tlie subtribe Älarieae. 
Chorda is only witb reservation referred to tbe familv 
(cf. also Reinke, 41), but tbat is a question of minor interest 
liere. Of tbe tliree species in tbe genus one is only found in tbe 
Baltic, tlie two otbers indeed are found in tbe Arctic Sea. Ch. 
Fiium at a good many different points, but not very far to tbe 
nortli, Ch. tomentosa only in yrestern Greenland. Tbis could 
speak for an atlantic origin, but as Ch. Filum is also found in 
tbe nortliern Pacific, tliere can bardly be tbougbt of any otlier 
original liome tlian tbe Polar Sea. 
Laminaria. Of tbis genus De Toni (14, HI) enumerates 
28 species (excl. Hedophyllum ), of wbicb 16 are indicated for tbe 
nortbern Pacific, 8 for tbe nortbern Atlantic, In tbe Polar Sea 
8 species sbould grow as indicated in fable I. Of tbese L. gro- 
enlandica. L. Agardliii, and perbaps L. solidungula are only 
arctic, tbe otber species are L. nigripes and L. saccharina , atlantic- 
pacific: L. digitata and . L. longicruris , someAvbat dubious as 
pacific plants; L. cuneifolia only pacific and arctic. Tbe atlan¬ 
tic species, tbat do not go into tbe Polar Sea, bowever are 
mostly restricted to tbe nortbern parts of tbe european coast L. 
hyperhorea, Gunneri , (discolor), hieroglyphica). One species, L. 
Bodriguezii is only found in tbe Mediterranean, tvro species in 
Soutli Africa ( L. pallida also at St, Paul and tbe Crozet Islands.) 
Tbe Pacific on tbe otlier band bas not less tban 10 species of 
its own, also Avitb a nortbern distribution. Indeed it cannot be 
denied tbat sucb a distribution can liave its cause in tbe circuni- 
stance tbat tbe genus vras Avidely spread already before tbe 
iceage, but tlien it becomes difficult to explain, wby not a single 
species goes fartber doAvn. in tbe Pacific (one species, L. himan- 
thophyll-a , indeed is mentioned from soutbern Soutli America by 
Po st eis and Ruprecht (39), but it is neA T er found again, and 
De Toni lias it among „species niaxime dubiae“). Tbe fact 
tbat tbe Laminariae are entirely absent from tbe tropic seas also 
points to a nortbern origin. Brom tliere tbe feAv soutbern forms 
must bave strayed during tbe iceage (cf. Setcliell. 48, p. 363. 
But Avby do Ave not bave any atlantic-pacific species, Avan- 
ting in tbe Polar Sea? I tbink tbe ansv^er must be: because 
tliere are different species forrned from tbe plivlembryons tbat 
baA^e occupied tbe tertiary Polar Sea and been driven soutbward 
into different areas. Tbat a lwely formation of new species 
bas taken place lately, or is still in progress, cannot be doubted 
Avlien tbe great number of nearly allied species is taken into con- 
sideration. tbat bas been distinguisbed by different autbors (cf. 
Setcliell. 48 p. 339). If tbe later Avriters are rigbt, avIio liaA'e 
ranged a great manv of tliem as sAmon\mis under comparatAeh' 
