Erythrocladia subintegra Rosenv.

Srythrooladia subintegra sd. nov. I. JC. Rosenvinge,
Danske ^id.Selsk. "Skr. vii. 7: p.73,figs.l?,14.1909
Thallus minutus suborbicularis. Fila sat regular-
iter radiantia, plerumque fere ad apices lateraliter
connata, cellulis tenninalibus tamen inter se plus
minus disc ret is. Ra-nificatio fit in cellulis termin-
alibus, saepe dichotoma. Cellulae plerumque cylin-
dricae, lat. 3—4 (—5)/u, long. 8—10,5>u.
Sporangia in parte proximali aut distali cellularura
orta diametro c.4(--5)/u.
In company with, the foregoing species I found some
individuals of a species evidently nearly related to
it, but showing however such differences that I think
it best to consider it as a distinct species. It is
more regular, more or less approaching to the orbicu-
lar form, and consits of more regularly radiating, closer
together and a little thinner threads (3—4 a), which
are most often united almost to the extremity, the term-
inal cells, however, being usually mo .re or less free,
and the same bein^j also sometimes the' case with the
cell next to the ^nd-cell. The ramification takes
place exclusively or principally in the end-cells, and
it has usually the character of a dichotomy, the cell
bifurcating with, two equally developed branches; the
one branch, however, may sometimes be stronger than
the other. The cell-walls of the filaments are thin
and often not easily distinguishable. In theinner
part of the cell-disc a granular substance is o"ten to
be seen in the in themiddle of the walls; perhaps
interstices between the filaments. The chromatophore
s».sjas t© la® of the same shape as in the foregoing
species, it i-s .parietal, apparently mantleshaped, and	(Continued page 74)
seems to con tain a pyrenoid; at all events a body of
greater density is often visible in the midale of the
cell. The cells are cylindrical or oblong or more
irregular, usually 2—3 times as long as broad, in
the inner part of the frond generally a little broad-
er than at the margin.
The sporangia are, as in E. irregularis, cut off
in the ordinary cells through a faintly curved wall,
sometimes at tile proximal, sometimes at the distal end
of the cell; they have a parietal, cupshaped chromato-
phore and measure 4Ax in diameter.
This species shows more resemblance than the pre-
ceding to the genus ICrythropeltis, from which it
differs, however', by the margin of the frond consisting
of separate filaments. If we supposed, that the dist-
inction established between these two genera might prove
not to be constant, the re would be reason to compare
5rythrocladia subintegra with Erythropeltis discigera
Schmitz. Such a comparison, however, is' difficult To
undertake, as the last-named species is imperfectly
knov/n, in particular on account of what is alluded to
above (p.72j with, regard to the limitation of the species.
Using the magnification indicated by Bert hold I have
calculated that the cells of his species are 5,5 to 7/u
broad, thus considerably broader than in E. subintegra,
and in Erythropeltis discigera va r. Flustrae Ba11.,
where the spores are much larger than in our species,
namely 9 u in diameter; the cells are also larger than
in E. subintegra. It must the refore be supposed that
the species described here has not hitherto been ob-
served, but I admit that it needs further investigation
as well as the species of Ery thro peltis and the
relation between this genus and the genus Erythroe 1adia,
and the relation between the genera Erythropeltis
and Hrythrotrichia.
The description given above refers only to the
specimens mentioned as found on Polysiphonia urceolata.
Later I have found, on Flustra i’cTliacea, some discs
which I think must be referred to the same species;
they differed in their slightly larger dimensions and
in the margin bein^ partly continous, the filaments
being united to the extremities. These discs were
thus still more similar to Erythropeltis, but the
filaments had always partly free endings. The fila-
ments were 3.5--S/i thick, narrowest at the border,
broadest in the middle of the frond. The spores were
4--5 /U in diameter.
Localities. 3k: Off Hirshals (XO and YKj, 11,5
to 15 meters, Aigust.
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