200 KJELLMAN, THE ALGA OF THE ARCTIC SEA. 
perfectly agree with the Greenland form. Further up in the streamlets where the water 
is but little brackish, it assumes a different aspect, becoming dwarfed, 2—3 inches high, 
with only the lower segments elongated, the upper ones being, on the contrary, very 
short and densely fasciculate; almost every segment of the last order bears a spherical 
receptacle, 2—38 mm. in diameter. 
Habitat.. This species is generally litoral, at least in the Norwegian Polar Sea 
and the immediately adjacent parts of the Arctic Sea. The form vadorum, however, is 
sublitoral, preferring sheltered localities. The others are to be found at exposed as 
well as sheltered places of the coast. I have already mentioned that I have found f. 
spherocarpa at the mouths of streamlets on the coast of Finmarken. Some of the forms 
grow in society, in large masses, contributing strongly to the character of the vegetation 
for considerable stretches. This is especially the case with f. typica and f. turgida on 
the north coast of Norway. All the forms mentioned have been taken in the Norwegian 
Polar Sea with receptacles in summer, June—August. I have seen specimens from 
Greenland with receptacles, collected in the month of July. Goxt reports f. angustifrons 
with receptacles from the White Sea, probably taken in summer. 
Geogr. Distrib. In consequence of the present species having been confounded 
with J. evanescens, it is impossible to decide its area of distribution by means of the 
accessible literature. I believe that it does not grow in any other parts of the Arctic 
Sea than the Norwegian Polar Sea, the western Murman Sea, the White Sea, and Baffin 
Bay, and that all F. vesiculosus which has been reported from other arctic regions is 
either F. evanescens or possibly some individuals of Ff’. vesiculosus which have drifted 
there from more southern parts. Such is probably the case with those fragments of 
F’, vesiculosus which were stated to J. G. AGArpu to have been collected at Spitzbergen. 
Cp. J. G. Ac. Gronl. Lam. and Fue. p. 30. The present species has no doubt its maxi- 
mum of frequency in the Norwegian Polar Sea. Already in the White Sea 7. vesicu- 
losus is less plentiful than I’. evanescens; see Gost, 1. c. p. 54. The extension of the 
species northwards is uncertain. 
Localities: The Norwegian Polar Sea: Nordlanden, f. vadorum common, f. typica 
common, f. angustifrons scarce, f. spherocarpa scarce; Tromsé amt: f. typica common 
and abundant at Tromsé, René, and Carlsé; Finmarken, f. typzca common and abundant 
at Maasd, Gjesver, the south coast of Magerd, Oxfjord, and Talvik; f. angustifrons local 
and scarce at Gjesver; f. turgida local, but abundant, at Maasé and Gjesver; f. sphe@ro- 
carpa scanty at Gjesveer. 
The Murman Sca: the coast of Russian Lapland (f. spherocarpa). 
The White Sea: f. angustifrons and f. spha@rocarpa less abundant. 
Baffin Bay: f. spherocarpa with certainty on the west coast of Greenland, as at 
Julianeshaab, Sukkertoppen, Godhayn, Rittenbenk, probably also at Egedesminde and 
in Cumberland Sound. Other reported localities dubious. 
The hybrid form /. serratus + vesiculosus has been found by Kieren at Nordlanden 
in the Norwegian Polar Sea. 
