KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND. 20. wN:0 5. 113 
In summer the plant always presents an aspect of this kind. J. E. Argscnouc 
in Ale. Scand. Exsicec. Ser. 2. N:o 57 has distributed such specimens, collected in August. 
Only exceptionally one finds some specimens of this kind during winter. 
The plant in winter habit. During winter and the earlier part of spring the plant 
has the appearance shown by fig. 2 and produced by all the clements of ramification 
being more or less completely dissolved. The elements 1 and 2 are most strongly re- 
sorbed. Specimens of this kind are very common on the coast af Bohuslin in winter 
during the months of December and January. 
The plant in spring habit. Fig. 3. Cp. Arescu. Alg. Scand. exsice. Ser. 1. N:o 54. Froin 
the portions that have persisted through the winter, branch-systems, sometimes scattered, 
sometimes somewhat tufted, are developed, which produce sporocarpia and tetrasporangia. 
These systems are decompound, with a coryinbose devclopment, and in this species attain 
a more considerable size before the ripeness of the spores, than in the preceding one. 
I do not know any antheridia in this species. I have taken specimens with ripe sporo- 
carpia in May, with ripe tetraspores in April. 
The structure of the frond. The figures 4 and 5, both representing sections of the 
lower part of the frond, show that outside the siphons there bevins a mighty layer of 
large-celled parenchyma, sharply defined without against a small-celled layer of tissue, 
that is also mighty and passes without marked limit into the cortical layer. All cell- 
walls are thick. The large-celled parenchyma is destitute of or poor in endochrome, 
the small-celled is rich in endochrome. 
It is evident, that of these two species Ph. virgata has nothing to do with Rh. 
lycopodioides. Rh. subfusca, on the contrary, presents so great a resemblance to certain 
forms of this species, especially f. typica /?. lara, that it may be questioned whether 
they are indeed specifically distinct. Both have very often been confounded with each 
other. All the specimens of the so-called Rh. subfusca, brought home by Kieren from 
Nordlanden and come under my notice, are undoubtedly forms of Rh. lycopodioides; 
and that plant from the coasts of Spitzbergen, which I have mentioned under the name 
of Rh. subfusca, 1 must now allow to be a form of Rh. lycopodioides. Many instances 
of that kind might be quoted. On that account, one might be inclined, like Gost, 
to unite these two Rhodomelw and to regard Rh. subfusca as a southern form of the 
other. But, on the other hand, it is remarkable, that both the forms occur quite cha- 
racteristical on the coasts of England, and that on the coast of Sweden Rhodomela 
subfusca, in whatever localities it may grow, whether near the surface or in deep 
water, is constantly alike in form, and, above all, never appears here in any densely 
branched compacta- or densa-form; whereas Rh. lycopodioides on the coast of Norway, 
when growing between tide-marks, exhibits regularly the form typica compacta, but in 
other cases assumes readily the aspect of f. typica /? laza, which proves that these two 
species or forms vary in a different manner. I must, moreover, call attention to a 
difference between them, which, as far as my researches go, has shown itself to be 
universal and constant. Rh. lycopodioides, in whichever of its numerous and extremely 
variable forms it may occur, always bears on its more robust axes short, slightly bow- 
K. Vet. Akad. Handl. Band. 20. N:o 5, L5 
