KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND. 20. N:o 5. 209 
doubtful to which of them a given form is rightly to be referred. But from this 
fact that certain forms of Fucus resemble one another, it does not in my opinion 
follow necessarily that they are phylogenetically allied. For although dwarfed forms 
of for inst. F. vesiculosus, I. evanescens, and I’. ceranoides happen sometimes to be so 
like as to make it hardly possible to establish any limits between them, yet these forms 
may be traced by intermediate ones into such forms as /’. vesiculosus f. vadorum, F. 
evanescens f. pergrandis, and F’. ceranoides f. typica, which will certainly not be regarded 
by any one as forms of one and the same species. I believe that the above-mentioned 
species of Fucus hitherto only little attended to, either are links of different series of 
forms or of the same series — perhaps one culminating in F. edentatus f. typica — or 
else are really different species. This point has not as yet been cleared up, and before 
this is done, it would be inconsiderate to unite the species in question into one. In 
such a case much more would have to be added to this collective species, and consi- 
stently all the northern Fuci must be thrown together into a chaotic whole — a mode 
af proceding which is certainly very convenient with regard to the systematization of 
a group rich in forms, but can hardly be considered satisfactory. 
Although I acknowledge sincerely that the plant, which I have called F. jiliformis 
and which according to the kind communication of J. G. AGarpu is identical with the 
alga thus named by him, is difficult to define sharply from other species, I do not 
think, however, that I am justified either by the experience acquired by examining a 
great number of living and preserved individuals or by reasons adduced by others to 
refer it as a subform to any other species. Accordingly, I retain it at present as a 
separate species. 
Habitat. This alga in company with /. distichus forms sometimes the principal 
vegetation in rock-pools within the upper part of the litoral zone. I have met with 
it both in exposed and sheltered localities. Its proper season of fructification on the 
north coast of Norway seems to be in June and July. It was found sterile in August 
and October on the coast of Finmarken. 
Geogr. Distrib. Known from the southern part of the Polar Sea north of the 
Atlantic. Its maximum of frequency is on the coast of Norway. The northernmost 
place where it has been found is Maasé, about Lat. N. 71°. 
Localities: The Norwegian Polar Sea: Nordlanden common; Tromsé amt, abundant 
at several places about the town of Tromsé; Finmarken: Maasé, Gjesveer, and the south 
coast of Mageré, pretty common and plentiful. Besides, it has been brought home 
from Krogoénis by Brrceren according to J. G. AG. 
The Murman Sea: the coast of Russian Lapland. 
The White Sea: at the Solowetzki Isles. 
Baffin Bay: the west coast of Greenland at Fridrikshaab and Rittenbenk. 
Of the two forms f. Gmelin is in my experience the more common one. 
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K. Vet. Akad. Handl. B. 20. No 5. 
