116 KJELLMAN, THE ALG^ OF THE ARCTIC SEA. 



Eh. lycopodioides f. setacea I have found only in one single place. It grew attached 

 to stones, in the interior of the deep Altenfjord, within the litoral zone at the mouth 

 of a stream. When gathered at the end of the summer, it was sterile. 



Rh. lycopodioides f. jiagellaris has been taken, in the latter part of July, within 

 the sublitoral zone, on shingly bottom on the north coast of Spitzbergen, in the interior 

 of a bay. It was then sterile. 



Rh. lycopodioides f. tenuissima. This form, the most common in the Arctic Sea 

 proper, always grows within the sublitoral zone, from near its upper limit to about 

 6 — 8 fathoms, attached to small stones, shells, or large algae. It is not seldom gre- 

 garious and very large masses of individuals occur Avithin small areas. It grows on 

 open as well as sheltered coasts. On the north coast of Spitzbergen it is found 

 throughout the whole winter and is in development during the whole year, although 

 only with the month of March a stronger and livelier formation of new vegetative parts 

 sets in. On the north-east coast of Siberia it has a period of rest during some part 

 of the year. This seems to be broken towards the end of June, as I infer from the 

 fact that in a great number of specimens which I had the advantage of examining 

 daily from the 7:tli to the 14:th of July, the older portions, that had persisted through 

 the winter, were clothed with new branch-systems in the first stage of development. 

 I do not know at what time the period of rest commences. Specimens taken in the 

 middle of September had already assumed their winter habit. At Spitzbergen the 

 plant probably bears its organs of reproduction, sporocarpia and tetrasporangia, 

 during the whole year. I have found specimens furnished with either of these or- 

 gans, in all the months of the year except May. They are most richly developed 

 during the latter part of July, during August, November and the commencement of 

 December; however, specimens with copious sporocarpia and tetrasporangia were found 

 even in January. On the west and east coasts of Novaya Zemlya I have collected 

 specimens with sporocarpia at the end of June and the beginning of August, and spe- 

 cimens richly furnished with tetrasporangia in the middle of July. Some specimens taken 

 in the eastern part of the Siberian Sea in the earlier half of July had no tetraspo- 

 rangia on the new branch-systems sprung from the winter plant. 



Geogr. Distr. The species, as understood in the above-mentioned comprehensive 

 sense, is probably circumpolar. But it is not as yet known from the American Arctic Sea. 

 The most northern place where it has been found, is Treurenberg Bay on the north coast 

 of Spitzbergen near Lat. 80° N. Within the Atlantic region of the Arctic Sea the ty- 

 pical form predominates, within the arctic region proper f. tenuissima, which is to be 

 regarded as one of the most characteristic alga3 of this region. 



Localities: The Norwegian Polar Sea: at Nordlanden common and abundant (f. 

 typica); at Finmarken common, but often in rather small numbers, as at Maaso, Ox- 

 fjord, Talvik; at some places abundant, for inst. at Gjesvaer and on the south coast 

 of Mager5 (f. typica); at Talvik also f. setacea was found. 



The Greenland Sea: f. cladostephus scarce and local, f. tenuissima common and 

 abundant on the north and west coasts of Spitzbergen ; t Jiagellaris at Treurenberg bay. 



