Siinmons, Remarks about tlie Relations of the Floras etc. 
189 
that can hardly ever be solved, as tlie most important evidence, 
the extinct forms, from which tlie now living Phaeosphoreae are 
derived, will never be brongbt forward, but for tlie present ob- 
ject it is of less importance. Otlierwise it is witb the question 
about the monophyletic or polyphyletic origin of the Lami- 
nariaceae. 
Reinke thinks that a monopliyletic origin must most pro- 
bably be assumed for them, even if he admits that rather weighty 
arguments can be advanced against it, such as the fact, that a 
Laminaria is quite as well adapted for its conditions of life as 
f. inst, a Lessonia , and that the different types grow together, 
especially in the Pacific. The most important evidence for the 
monophyletic origin is that all other forms during their ontoge- 
nesis have to pass a ^Laminaria- stageh But there are facts, not 
mentioned by Reinke, that must be taken into consideration, 
and which in my opinion turn the balance in favour of the po¬ 
lyphyletic origin of the family. 
If tlie genus Laminaria was the original one, from which 
all tlie others are derivates, it must be assumed that Laminaria 
has several tim es given birth to new types, while as well the 
primeval L. solidungula as other Laminaria- species, that have 
tlirougli „explosion“ (Reinke) given rise to new species and ge- 
nera still live, notwithstanding the very long ages that must 
have passed since the differentiation from L. solidungula of f. 
inst, the phylembryons of Macrocystis or Lessonia took place. 
Indeed such a thing cannot be declared impossible, but mostly 
those old types will be found to stand rather isolated, as we see 
in the case of such plants as can be followed some way back in 
the geological record, f. inst, tlie Gymnospermae , the Amentaceae 
and others. The genera usually are well defined, the species 
likewise, and mostly the latter are few or there is only one 
species to the genus. I think there can hardly be brought for¬ 
ward any evidence of an old type, that has for äges lived be- 
sides its heterogenous offspring and than abruptly entered a new 
period of mutation. But that decidedly should be the case witli 
Laminaria if Reinke was right; there we at present have a 
rather great number of little differentiated species, that cannot 
very long ago have branched off from their common progenitors. 
Moreover it can hardly be thought, especially when the distri- 
bution of the genus Laminaria as it now is, is taken into con¬ 
sideration, that a species that is now exclusively arctic should 
be the ancestor of all the genera of Laminariaceae now living 
solely outside the arctic regions, or even restricted to Southern 
waters alone. 
It seems to me quite impossible to assume a monophyletic 
origin for the whole family from Laminaria solidungula, On 
the contrary I am inclined to look upon the highly organised 
genera, or at least their hypothetical Laminaria- like ancestors, 
as much older tlian any now existing Laminaria. How far back 
we must go to find the common phylembryons of Laminaria 
