110 KJELLMAN, THE ALGtE OF THE ARCTIC SEA. 



ine to adinit that this plant, so sharply distinguished in its purely arctic form from 

 Rh. lycopodioides, is yet so nearly related to it tiiat no definite limits can be drawn 

 between thera. Besides, 1 must concede, on the other side, that the uniting of Rh. 

 lycopodioides and Rli. suhfusca insisted on by Gobi, however unnatural it may appear 

 at first, has nevertheless a great probability, considering the number of diverse forms 

 under which Rh. lycopodioides appears, several among which come extremely near Rh. 

 suhfusca (WooDW.) Ag. However, in this admission I must make a decided restriction. 

 By the excellent works of J. E. Areschoug Swedish algologists have been made well 

 acquainted with the fact that there are to be found on the west coast of Sweden three 

 forms of Rhodomela, one characterized by the just mentioned algologist as, forma extra- 

 tceniensis et normalis, the second as forma intratceniensis proicedentis magnitudinis et 

 crassifiei, the third as forma gracilis. Areschoug regards all three as forms of Rhodo- 

 mela suhfusca (WooDW.) (see Aresch. Obs. Phyc. 3, p. 6). All have been distributed 

 in magnificent specimens in Alg. Scand. exsicc. under N:o 57, 58, 303, Ser. 2 and N:o 

 54 Ser. 1. I have had an opportunity of more closely examining living specimens of 

 the two first of these in different stages of development and at different times of the 

 year, and I have found them to disagree so essentially in habit, morphological deve- 

 lopment, anatomical structure, and biological conditions, that I must account them 

 different species, if indeed any species of Rhodomela are to be distinguished at all. 

 Only one of these two can be regarded as nearly related to Rh. lycopodioides; the 

 other is surely sharply distinct from it. In order to be able to exposé this question 

 more fully, I think best to give already here a description of these two Swedish species 

 of Rhodomela, although this does not belong strictly to the immediate subject of this 

 work. I shall begin with the above-mentioned forma intratceniensis. As far as I can 

 see, it has not been described or figured under any specific name, at least not so as to 

 be recognizable. I propose to name it Rh. virgata. 



Rhodomela Virgata novum nomen. 



Tab. nostra 7. Exsicc. Aresch. Alg. Scand. exsicc. N:o 303. 



Description. A sjmng jdant of the first year, according to a specimen from Bohus- 

 län taken in the middle of May; fig. 1. About 20 cm. high; when dry, with flat main 

 stem and flat primary branches, which do not become black; of a i^ed-brown colour. 

 The hold-fast is a callus radicalis. The frond is distinctly repeatedly racemosely branched. 

 A main axis is distinguishable throughout the whole frond; it attains its greatest thick- 

 ness at the middle, tapering rather swiftly towards the summit, gradually towards the 

 base, abruptly only in the vicinity of the hold-fast. Throughout its whole length, it 

 bears branch-systems, diminishing upwards in length and strength. The lower ones 

 have a lanceolate, the upper ones an ovato-triangular periphery. The main axes of the 

 lower larger branch-systems are thickest at the middle and taper strongly towards the 

 tip as well as towards the base. At the point where they branch off from the main 

 stem, their thickness is considerably smaller than that of the stem. The lower lateral 

 axes of the first order carry few and very tinely decompound, short, branch-systems 



