KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND. 20. N:0 5. 177 
from the outer Norse Isle and on the north-western coast of Spitzbergen, f. litoralis 
from the Norwegian Polar Sea at Maasd. 
Gen. Callithamnion (Lynce.) Tuur. 
in Le Jou. List. Alg. Cherb. p. 17; Lynos. Hydr. Dan. p. 123; lim. mut 
Callithamnion polyspermum Bonnem. 
in Ag. Spec. Alg. 2, p. 169. 
Descr. Callithamnion polyspermum J. G. AG. Epier. p. 32. 
Fig. Phlebothamnion polyspermum Kutz. Tab. Phye. 11, t. 97. 
Syn. Callithamnion polyspermum Kieren, Nordl. Alg. p. 22. 
Remark on the determination of this species. The individuals from the Polar 
Sea that I have seen, agree more with the quoted figure in Kirzic, than with 
the figure on pl. 231 in Harv. Phye. Brit. They differ from English specimens by 
being less decompound, so that those branch-systems which are called plumul@ in 
the descriptions are comparatively rare, being supplied by simple branches. From this 
cause those arctic specimens present an aspect differing from typical C. polyspermuim. 
However, they ought probably to be referred to this species. This is also the opinion 
of KLEen. 
Habitat. Pelagic, growing scattered, fastened to litoral algw, as Polysiphonia fasti- 
giata, Furcellaria fastigiata, and Rhodymenia palmata. It has been found with scarce 
tetrasporangia at Nordlanden in August. 
Geogr. Distrib. Found only within the Atlantic region of the Polar Sea. 
Locality: The Norwegian Polar Sea: Nordlanden in several places. This is the 
northernmost place where it is known to grow. 
Callithamnion Hookeri (Dimtw.) Aa. 
Spec. Alg. 2, p. 190. Conferva Hookeri Ditiw. Brit. Conf. t. 106 see. Ag. 1. e. 
Deser. Callithamnion Hookeri J. G. AG. Epier. p. 33, 
Fig. Phlebothamnion Hookeri Kurz. Tab. Phye. 11, t. 94. 
Eesice. Callithamnion Hookeri Arescn. Alg. Scand. exsiee. N:o 311. 
Syn. Callithamnion THookeri Kingen, Nordl. Alg. p. 21. 
Halitat. In that part of the Polar Sea where it has been as yet observed, this 
plant is litoral, growing attached to Polysiphonia fastigiata. It has been found here 
with tetrasporangia in June, with sporocarps in July. 
Geogr. Distrib. Known only from the southern border of the Polar Sea. 
Locality: The Norwegian Polar Sea: Nordlanden at Bodo. 
K. Vet. Akad. Handl. Bd 20. N:o 5. 
