KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND. 20. N:0 5. 171 
Phyc. Brit. This must be the form recorded by J. G. Ac. under the combined names 
of C. rubrum 4 pedicellatum. It seems to be easy to recognize by having numerous, 
but short and not dichotomously compound lateral branches. This form leads over to 
f. prolifera with its more or less richly prolificating thallus. Some of the specimens 
from the Polar Sea, that I have seen, are most nearly related to the Ceramium secundatum 
figured by Lynenyr, others to Harvey’s C. botrycarpum. Of all the arctic forms that 
one which I have kad delineated in table 15 fig. 7, is perhaps the most peculiar. I 
have thought to recognize in it a form of C. rubrum described by Harvey under the 
name of f. sguarrosa. It is a small-sized, rather slender form, most easily recognizable 
by the upper segments being strongly spreading from one another, those of the last 
order, which bear tetrasporangia, being recurvate. 
Habitat. In the Norwegian Polar Sea this alga is mostly litoral, in the other 
parts of the Polar Sea that I have myself examined, it is sublitoral, belonging here to 
the Laminariace-formation. It is generally attached to other algw, growing scattered on 
exposed coasts, and more abundant in sheltered localities. At Nordlanden it has been 
found with sporocarps and tetrasporangia during all summer, at Spitzbergen with tetra- 
sporangia at the end of July and the beginning of August. At Novaya Zemlya and 
Waygats in June and July, and at Finmarken in July, August, and September, I have 
met with only sterile individuals. At Russian Lapland, on the coast of Cisuralian Samoyede- 
land, and in the White Sea, it appears often to bear plenty of tetrasporangia in summer. 
Geogr. Distrib. It belongs to the Atlantic as well as the arctic region of the 
Polar Sea, reaching its maximum of frequency within the southern part of the former 
aud not being widely spread within the latter. Its northernmost known place of growth 
is on the west coast of Spitzbergen about Lat. N. 76° 30’. 
Localities: The Norwegian Polar Sea: Nordlanden, common and plentiful; Fin- 
marken, pretty local and scanty at Gjesver and Talvik. 
The Greenland Sea: the west coast of Spitzbergen, generally local and scanty, in 
one place abundant. 
The Murman Sea: the coast of Russian Lapland and Cisuralian Samoyede-land; 
Kolgujew Isle; the west coast of Novaya Zemlya and Waygats, from M. Karmakul Bay 
to Jugor Shar, local and scarce. 
Baffin Bay: the west coast of Greenland: Neuherrnhut, Godhavn. 
At Nordlanden all the forms mentioned are to be found. North of this region 
only f. decurrens and f. genuina are met with, most commonly the former or transitions 
between this and the typical] form. 
Ceramium acanthonotum Carn. 
in J. G. Ac. Advers. p. 26. 
f. typica. 
Deser. Ceramium acanthonotum J. G. Ac. Epier. p. 103. 
Fig. » » Harv, Phyc. Brit. t. 140. 
Eusice. » » ArescH. Alg. Scand. exsice. N:o 12. 
