DR. Е, BÜRGESEN ON FUCUS SPIRALIS, LINNÉ. 113 
Both these species are hermaphrodite, and some of their forms may give 
rise to difficulties * when studied in the herbaria ; but in nature, where these 
species oceur together, it will always be easy to decide to what species а given 
specimen belongs, as they grow at different tide-levels, viz. : Fucus inflatus 
on sheltered coasts at about low-water mark, while Fucus spiralis occurs at 
about high-water mark. As before said, I dare not say anything decided 
as to this specimen; the long receptacles suggest Fucus inflatus, while the 
short roundish ones might belong to Fucus spiralis, L. : possibly we have to 
do with a bastard of these two species. 
Even if one of Linné's specimens is doubtful, it is my opinion that we 
have sufficient support in the other typical specimen ; no doubt most herbaria 
have, besides typical specimens, others also more or less differing. At all 
events the Linnean specimens show that they have nothing in common with 
Fucus vesiculosus, and Prof.. Sauvageau's chief complaint against Fucus 
spiralis, L., that this included also forms of Fucus vesiculosus, is thus not 
supported by Linné’s herbarium. 
Finally I want to emphasize a point which 1 find is highly in favour of my 
opinion, namely :—that Linné, in the group of Fucus, which he describes as 
* Dichotomi fronde:centes," has the following six species : serratus, vesiculosus, 
ceranoides, spiralis, inflatus, and divaricatus. With the exception of the last 
mentioned, which is a form of Fucus vesiculosus rich in vesicles, the species 
which Linné was clear-sighted enough to recognize have remained till to-day. 
One may contrast with this the great number of species which J. Agardh 
has in “ Bidrag till kännedomen af Spetsbergens Alger? (К. Vet.-Akad. 
Handl. vol. vii. no. 8, р. 31), and which, for a long time, brought confusion 
into the systematies of the genus Fucus. 
Strictly speaking, I could very well stop here, as I think, from what has 
been already written, that we have gained a sufficiently clear idea of Fucus 
spiralis, L. ; but as it is of interest to follow the history of this species to the 
present day, and as Г do not quite agree with Prof. Sauvageau's representation 
of this also, I shall here enumerate the chief facts. 
К. G. Gmelin mentions (* Historia Fucorum,’ Petropol. 1768, p. 62) Fucus 
spiralis as a variety of his Fucus Quercus marina= Fucus vesiculosus, L., 
while he, in the 13th edition of ‘Systema Nature,’ 1791, р. 1386, has Fucus 
spiralis as a distinct species, but adds: “ An vesiculosi varietas ? "' 
While Hudson (*Flora Anglica, editio altera, tom. 2, London, 1778, 
р. 577) only copies the diagnosis of Linné in ‘ Systema Nature,’ edit. 12, 
Lightfoot, on the contrary, has an excellent description of this species in 
‘Flora Scotica? (London, 1777, vol. ii. p. 911). 
* Compare for instance Setchell and Gardner, “ Algæ of North-Western America," p. 281, 
and Yendo, “ The Fucaceæ of Japan," where the forms which he calls Fucus evanescens and 
of which he gives an illustration (pl. 1. figs. 1 & 2) highly resemble Fucus spiralis. 
