106 DR. Е. BORGESEN ОХ FUCUS SPIRALIS, LINNÉ., 
example: De Toni’s * Sylloge Algarum, vol. iii., where we find Fucus platy- 
carpus, Thuret, p. 205, Fucus vesiculosus var. limitaneus, Mont., pp. 206-7, and 
Fucus spiralis, L., р. 207. 1 am pleased to see that Prof. Sauvageau quite 
agrees with me as to the definition of the species. 
In * Botany of the Færöes, I have written as follows :— 
“Fucus SPIRALIS, Linné, Flora Lapponiea, р. 850, No. 467; Species 
Plantarum, Tom. ii. p. 1159, Holmiæ, 1753: Systema Nature, Editio 
duodecima, Tom. ii. p. 715, Holmiæ, 1767; Kjellm., №. I. p. 252 (202). 
Fucus plitycarpus, Thuret, Études phyeolog. р. 70. Fucus Areschougi, 
Kjellm., Handb. p. 11. Fucus vesiculosus B. spiralis (L), Lyngb., Hydrophyt. 
р. 3 (according to the specimens in his herbarium in Copenhagen). 
f. TYPICA. Fucus Areschougü, Kjellm., the main form, Handb. l с. 
# NANA, Kjellm.. Handb. р. 11; Fucus limitaneus, Mont., Thuret, l e. 
, J H H d H 3 
рр. 41-42; Fucus platycarpus, var. linutaneus, Sauvageau, Sur les 
Aleues du golfe de Gascogne, p. 35 (Journal de Botanique, vol. xi. 
р. 268). 
“Tam quite convinced that all the species mentioned here and deseribed 
by different authors (some more may be added to the list, cfr. e. д. Thuret and 
Kjellman, l. е.) must be regarded as belonging to Linnés old species Fucus 
spiralis.  Linné’s description in the works quoted 13, though short, vet fairly 
exhaustive, so a sufficiently clear idea may be formed of what he meant. 
“ Now the alga named by Thuret Fucus platycarpus and figured by him 
on tab. 16: l. e.—original specimens of which were very kindly sent to me 
from Thuret’s herbarium by Prof. Sauvageau—differs rather considerably 
from what, e. g, Kjellman calls Fucus Areschougit, and of which a typical 
example is to be found in Areschoug’s Exsice. No. 54 (compare also my 
figure 04 *). But to this I may remark that both in the Firth of Forth near 
North Berwick, and at Heligoland I gathered specimens which are exactly 
intermediate between these. And even among my Færöese material I found 
a very few specimens ог portions of. plants which reminded one strongly ot 
Fucus platycarpus, Thur., e. g., the portion of the plant. given in fig. 95 f, the 
other part of the same plant being like the main species, My opinion is, that 
Thuret's Fucus platycarpus is a more southerly variety of Fucus spiralis, 
while the typical form occurs more particularly in the northern regions, but 
may also be found growing together with var. platycarpa in the southern, 
I would point out as particularly characteristic of var. platycarpa that its 
main branches are distinctly continued along its whole length, while 
Fucus spiralis, L., typica—as I regard it, and to which as I said before 
* Т.е. Но, 1 of the present paper. t Fig. 2 on p. 108. 
