I
t
Si: r
Ser. Chlokospermea5. Fam.
P l a t e CXXXV.
CLADOPHORA ARCTA, Kiitz.
Gen . C h a r . Filaments green, jointed, attached, uniform, branched. F ruit,
aggregated granules or zoospores, contained in the joints, having at
some period a proper ciliary motion. C ladophora [Kiitz.),—^from
kKcSos, a hraueh, and fiopia, to bear.
C ladophoea arcta-, filaments forming broad, starry tufts, of a brilliant
green colour, much branched, and more or less matted together below;
rranches straight, crowded, very erect; ramuli appressed, opposite or
alternate, scattered; articulations in the older parts once or twice as
long as broad, in the young (upper) branches many times longer.
C l a d o p h o e a arcta, Kiitz. Phyc.. Gen. p. 363.
C l a d o p h o r a vauchcriaeformis, Kiitz. I. c. p. 368.
Cladophora centralis, Kiitz. I. c. p. 369.
C o n f e r v a arcta, Billw. Conf. Suppl. p. 67. t. E. K. Pot. t. 2098. lyjngb.
Hyd. Dan.-g.161. Ag. Syst. p. 118. Harv. in Hook. Br. FI. vol. ii.
p. 359. Harv. in Mack. FI. Hib. part 3. p. 230. H a n . Man. p. 139.
C o n f e r v a centralis, Lyngb. Hyd. Dan. p. 161. t. B6. Ag. Syst. p. 111. FI.
Dan. t. 1777. Harv. in Hook. Br. FI. vol. ii. p. 358.
Conferva vaucheriEeformis, Ag. Syst. p. 118.
H a b . On exposed snb-marine rooks from half-tide level to low-water mark.
Perennial ? Spring, summer and autumn. Frequent on the British
shores from Orkney to Cornwall.
Geogr . D is t r . Abundant on tbe Atlantic sbores of Europe and nortb America.
Baltic Sea. Falkland Islands, Dr. Hooker.
D esc r. Tufts rising from a spongy, cusbion-like base, spreading in a circle,
more or less split, in a starry manner, into several minor bundles, wbicb
are either simple or divided in a fan-like or palmate manner above. Filaments
slender, flaccid, mucb branched, tbeir lower portions more or less
matted together according to age, connected by irregular, root-like fibres,
wbicb issue from tbe lower branches, and twine among tbe neighbouring
filaments; brandies very straight, and erect, somewhat pencdlate, repeatedly
divided, tbe lesser divisions alternate, or scattered, all very straight and
erect. In young specimens, and also in those of tbe second season, after
tbe new growth commences, tbe uppermost branches are much produced, of
a very vivid green colour, and distinguished by having very long joints ; at
a later period these disappear, and the tufts become fastigiate, and very
matted together, like a sponge. ^ Colour a rich, deep green, occasionally
somewhat glaucous, fading and losing mucb of its gloss in tbe herbarium.
Substance, when young, tender and flaccid, closely adhering to p ap e r; when
old, more or less membranaceous, and very imperfectly adhering to paper.
VOL. I I .