G e n u s XXXIX. GIGARTINA, Lamour. Tab. XVI.
G e n . C h a r . Frond horny or cartilaginous, filiform, cylindrical,
irregularly branched. Fructification uniform : spherical
sessile capsules containing a globose mass of seeds.
O b s . The most imperfect of all the genera proposed by Lamouroux
was that denominated by him Gigartina, a name derived from a Greek
word signifying a grape-stone, or, according to his view, the grape itself,
because the capsules were mostly semitransparent- The species
to which I propose to limit it are comparatively few, and mostly contained
in the seventh section of the genus Sphoerococcus, as it stands
in the Agardhian System. They are conspicuous for their filiform,
tufted, and generally rigid mode of growth, a purple red colour often
approaching to black. The fructification, as far as it is known, is composed
of sessile spherical capsules, containing a mass of ovate or
roundish free seeds, imbedded in gelatine. In G. plicata, Griffithsioe,
congesta, spinella, ustulata (a doubtful species), dmergens, and subu-
lata, capsules have not been observed. Fucus helminthochorton of
La Fourette, I am compelled to allow to remain among the Gigartinæ
for the present, as the fructification, scarcely ever seen, does not exist
in my specimens. The structure of the frond, however, is very peculiar,
being exceedingly lax and cellular, with a consistence similar to that
of the stems and leaf-stalks of some aquatic herbaceous phænogamous
plants, and having the appearance of articulations which do not actually
exist. I consider this Alga, sui generis. Nematliecia are found on
Gigartina plicata and Griffithsioe, and have been described by authors
as wart-like fructification.
1. G ig a r t in a p i s t i l l a t a .
Frond cartilaginous filiform subcylindrical or compressed subdicho-
tomous the branches set somewhat distichously with short subulate
horizontal ramuli, capsules near the apex of the ramuli.
Gigartina pistillata, L am o u r . E s s a i. p . 49. G a ill. D i e t . S c . N a t . v . 53. p . 365.
Fucus pistillatus, G m e l. H is t. F u c . p . 1 5 9 .1 . 18, f . 1. L am o u r . D is s e r t, p . 51. t . 27.
Fucus gigartinus, L in n . S y s t. N a t . v . 2. p . 719. G o o d e n , a n d W o o dw . in L in n . T r a n s .
V. 3. p . 183. t . 17, f . 3 , 4. b a d . Sm . E n g . B o t. t . 908. T u m . S y n . F u c . p . 280. H is t.
F u c . t . 28. e x c e lle n t.
H a b . In the sea. Perennial. Spring. Very rare. Coast of Cornwall,
Dr Wenman. Mounts-Bay, near Newlyn, Dr Macculloch.
Rocks near Padstow, Miss Hill.
Root a flat disk. Fronds tufted, three to six inches in length, generally
more or less compressed, but sometimes almost cylindrical,
filiform, one or two lines in diameter, branched a few times in an irregularly
dichotomous manner, naked below, but producing on the upper
parts numerous subulate ramuli, two lines to half an inch long,
arising horizontally in a somewhat distichous arrangement. Capsules
sessile, as large as turnip-seed, solitary, or two or three together, lateral
on the subulate ramuli, rarelv terminal ; composed of a cellular
transparent coat, and a dark red internal mass, formed by a number of
little distinct ovate parcels of angular seeds. Substance cartilaginous,
hard and horny when dry. Colour a dull bluish purple. It does not
adhere to paper.
One of the rarest of the British species, and confined to tbe shores
of Cornwall. The station of St Ives, however, recorded by Goodenough
and Woodward in the Transactions of the Linnean Society, is
erroneous, as we are informed by Sir J. F. Smith, in Fnglish Botany.
Loefling gathered the plant at St Uhes, in Portugal, and communicated
specimens to Linnæus, in whose Herbarium St Ives was read by mistake
for St Uhes. The fructification is curious,, and in the seeds being
collected into distinct parcels, differs from all the other F lo r id eæ
I am acquainted with.
2. G i g a r t i n a a c i c u l a r i s . Tab. XVI.
Frond cartilaginous cylindrical filiform subdichotomous, the branches
somewhat pinnated with horizontal elongated acuminated ramuli, capsules
spherical sessile scattered.
Gigartina acicularis, L am o u r . E s s a i, p . 49» G a ill. D ie t . S c . N a t . v . Ô3. p . 365.
Sphoerococcus acicularis, Ag. S p . A lg . v . 1. p . 322. S y s t . A lg . p . 237-
Fucus acicularis, W u l f e n . C r y p t . A q u a t N o . 50. T u m . H is t. F u c . t . 126. Sm . E n g .
B o t. t . 2190.
H ab. On rocks in the sea. Annual ? Winter. Cornwall, very rare,
Mr W. Rashleigh. Ilfracombe, Lupton Cove, and near Torquay,
Mrs Griffiths. Sidmouth, Miss Cutler.
Root a minute disk. Fronds tufted, two to four inches in height,
divided somewhat distichously into spreading branches of nearly equal
length, so as to form a roundish general outline ; branche; cylindrical,
about half a line in diameter, acuminated, either again divided dicho-
tomously or irregularly, or pinnated with acute ramuli from a few lines
K 2
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