172 KJELLMAN, THE ALGiE OF THE ARCTIC SEA. 



f. coronata Kleen. 



Nordl. Alg. p. 19. 



Descr. Ceramium acaathonotum var. coronata Kleen 1. c. 



Fig. a » 1) » 1) t. 10, fig. 6. 



Reviark on the form coronata. In Kleen's collections only the typical form of 

 Ceramium acanthonotum is to be found, but some specimens have the spines in certain 

 parts of the frond so arranged as in the variety distinguished by Kleen. This variety 

 resembling the typical form in all other respects: branching, colour, structure of the 

 cortical layer, shape and disposition of the tetrasporangia etc., it may be considered 

 as rather little independent, though it deserves perhaps to be specially mentioned. 



Habitat. This alga is literal, pelagic, and somewhat gregarious in the Polar Sea. 

 It keeps chiefly to such places as are left dry at low-tide, but is also to be found in 

 rock-pools between tide-marks. In the localities where it has been observed as yet, it 

 bears plenty of tetraspores in July and August. 



Geogr. Distrib. Known only from the southern part of the Atlantic region of the 

 Polar Sea. 



Locality: The Norwegian Polar Sea: Nordlanden, common and abundant. This is 

 the northernmost known locality of the species. The form coronata has been found 

 together with the typical form. 



Gen. Ptilota (Ac.) J. G. Ac. 



Spec. Alg. 2, p. 92; Ag. Syu. Alg. p. XIX: ex parte. 



Ptilota elegans Bonnem. 



Hydr. loc. p. 22, sec. J. G. Spec. Alg. 2, p. 94. 



Descr. Ptilota elegans J. G. Ag. Epicr. p. 74. 



Fig. » sericea Harv. Phyc. Brit. t. 191. 



ExsicG. » elegans Aresch. Alg. Scand. exsicc. N:o 11. 



Si/n. Ptilota elegans Kleen, Nordl. Alg. p. 20; excl. syn. 



Habitat. The present species is litoral, pelagic, and somewhat gregarious, and 

 usually grows on steep rocks between tides under beds of Fucus and Ozothallia, or on the 

 walls of grotto-shaped cavities, which it covers, in company with Delesseria alata, with 

 a dense mat. Even on the coast of Finmarken it reaches a considerable size. 1 have 

 seen very luxuriant individuals more than 10 cm. high near North Cape. In the Nor- 

 wegian Polar Sea it bears tetraspores during the summer, sporocarps in August. 



Geogr. Distrib. This species belongs to the Atlantic region of the Polar Sea. Its 

 most northern known locality is Gjesva'r about Lat. N. 71°. 



Localities: The Norwegian Polar Sea: Nordlanden, scarce. Finmarken: MaasO, 

 Gjesvajr, Oxfjord, local, but pretty abundant. 



