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Ge n u s X X X III. GASTRIDIUM, Lymjb. Tab. XIV.
Ge n . Ch a r . Frond cylindrical, filiform, (often contracted as
if jointed), between gelatinous and cartilaginous, of a
pinky red colour. Fructification of two kinds ; 1. spherical
ovate or conical capsules with wedge-shaped or angular
seeds; 2. imbedded ternate granules.
O bs. The species of this genus constitute part of the first and third
sections of Lamouroux’s genus Gigartina. In Lyngbye’s System they
belong partly to Lomentaria and partly to Gastridium-. Although
very indefinite in the author’s work, and intended to include plants
that have no affinity with each other, I have adopted the name in preference
to any new one. It is sufficiently expressive of the habit of
the species, which are turgid with fluid, and may be compared to a
hollow membrane distended with its contents. I must also observe
that the present genus was comprehended hy the Chondria of my
friend Agardh, whose name I should have retained, had it not interfered
with the earlier genus Chondrus, bestowed upon another group
by the late Professor Lamouroux.
If we consider the fructification of these plants, two genera appear
to be indicated: but in every other respect, there is so great a similarity,
that, in the present state of our knowledge, at least, it would be
doing violence to nature to separate them. In Gastridium kaliforme
and ovale, the capsules are globose, with a pellucid border, without a
terminal pore, the interior filled with a most dense red mass of wedge-
shaped seeds radiating from a central point at the bottom of the capsule.
The same holds good in regard to G. parvulum, except that
the capsule is ovate, and without a pellucid border. The capsule of
G. uvarium, at present unknown, will probably he found of a similar
nature. In G. davellosum and articulatum, on the contrary, the capsules
are obtusely conical, without any pellucid border, furnished with
a terminal pore, and contain a conical mass of angular seeds. It will
be perceived how ill the species of the preceding genus would associate
with the present individuals,—difl'ering, as they do, not only iu
fructification but in habit.
All the British species, except G. clavellosum and ovale, are contracted
at regular intervals as if they were jointed. The colour of the
frond varies from a fine pink to an orange-red or brick red, often acquiring
a gi-eenish tint in decay, and at length becoming white, The
root is between scutate and fibrous.
* Frond without contractums.
I. G a s t r id iu m c l a v e l l o su m .
Frond gelatinous much branched branches distichous repeatedly
pinnate the ultimate ramuli more or less lanceolate attenuated at their
base, capsules conical.
Gastridium clavellosum, L y n g b . H y d r o p h . D a n . p . 70. t. 17-
Chondria clavellosa, A g . S p . A lg . v . 1. p . 353. S y s t. A lg . p . 206. G r e v . F I. E d in . p . 291.
S p r e n g . S p . P I . v . 4 p . 342.
Gigartina clavellosa, L am o u r . E s s a i, p . 49.
Fucus clavellosus. T u r n , in L in n . T r a n s , v . 6. p . 133. t . 9. H i s t . F u c . t . 30. Sm . E n g .
B o t . t. 1203.
V a r . /3 sedifoHus, r a m u l i b e tw e e n o b lo n g a n d o v a l , c row d e d , u n d iv id e d , T u m .
Gastridium purpurascens, L y n g b . H y d r o p h . D a n . p . 69. t . 17.
H a b . In the sea. Annual. May to September. Scarborough,
Sir Thomas Frankland. Beach at Yarmouth, Mr Wigg. Sunderland
beach, Mr Weighell. At Gunton and Gorton, Suffolk, Mrs
Fowler. Coast of Cornwall, and at Torquay, Mrs Griffiths. Dublin
Bay, Dr Scott. Bantry Bay, Miss Hutchins. Larne, near Belfast,
Dr Drummond- Frith of Forth. Isle of Bute. Var. g at Lossiemouth,
Mr Brodie. Bantry Bay, Mr J. T. Mackay.
Root a minute disk. Frond mostly solitary, three to twelve inches
in height, much branched in a bushy manner, the main stem often as
thick as a crow-quill: branches alternate, distichous, the lower ones
sometimes as long as the entire frond, repeatedly pinnate, somewhat
attenuated, but rarely acute at the extremity, the ultimate ramuli one
or two lines long, more or less lanceolate, tapering much at their base,
and arranged in a distichous manner along the primary as well as all
the other hranches. Fructification ; 1. obtusely conical capsules furnished
with a pore, containing a conical mass of red angular-ovate
seeds: 2. ternate granules in the lanceolate ramuli, on distinct plants.
Substance gelatinous and tender, adhering to paper in drying. Colour
a beautiful fugacious pink, yellowish white or greenish in decay.
The ramuli of this elegant species are liable to considerable variation
; the most common form is perhaps linear-lanceolate, but they are
sometimes ovate-lanceolate, and in Mr Turner’s singular variety they
are said to resemble the leaves of Sedum sexangulare. They are alii
2