The English flora - SeaweedAfrica

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Catenella.] ALG7E I NARTICULAT7E. 309
Ag. Sp. Alg. v. \. p. 214.— Gastridium filiforme, Lyngb.— Viva
purpurascens, E. Bot. t. 641.— Ulva incrassata, U. sponyiformis,
and U.JUiformis, Ft. Dan.—;3. crispata ; frond compressed
waved curled and twisted, of a brownish-purple colour.
Grev. I. c.—Holymenia purpurascens, var. crispata, Grev. Crypt.
Fl. t. 240.
On rocks and stones in the sea, frequent.— /3. Firth of Forth, Dr.
Greville. Firth of Clyde, at Helensburgh. 0. Summer.
45. Catenella. Grev. Catenella.
Fronds filiform, somewhat compressed, creeping, throwing
up numerous branches, contracted, as if jointed, in a moniliform
manner, composed interiorly of branched filaments radiating from
the centre. .Fructification unknown. Grev. Alg. Brit. p. 167.
t.\7.—Name; catenella, a little chain, which its fronds resemble.—
In deference to Dr. Greville, I adopt this Genus ; but its
fructification is wholly unknown. Mr. Harvey, too, observes
in a letter to me, " I confess I would rather leave this plant in
Chondria (Gastridium, Grev.) until the fructification be discovered,
as it perfectly agrees with the other species in habit,
and, unless I greatly err, in structure also. When at the coast
I took some pains, struck with the similarity in habit between
the Gastridia and C. Opuntia, to dissect, as minutely as I was
able, the fronds of G. articulation, as being the species most near-
ly allied (externally) to the plant in cpiestion ; and the result
was a conviction on my part that the structure was precisely
similar. I found the pseudo-joints full of very lax gelatine, in
which articulated filaments appeared to be loosely floating, fixed
only to the periphery, though I presume, originating in a central
point ; but my instruments were not sufficiently delicate to dis-
sect them without laceration ;
neither has Dr. Greville been able
to do so with C. Opuntia. The filaments themselves are colourless,
arachnoid, much branched in a dichotomous manner."
I. C. Opuntia, Grev. (Opuntia-like Catenella).— Grev, Alg.
Brit. />. Ki6. t. 17. Chondria Opuntia. Book. Scot, P. II.
p. 106.— Halymenia Opuntia, Ag. Sp. Alg. r. 1. j). 217.
Gigdrtina Opuntia and pilosa, Lamour Rivularia Opuntia,
H. Hot. t. 1868.-— Chordaria opuntia. Spring.— Lomentaria
Opuntia. (iaill.— FuCUt Opuntia. Ootid, and Woodw. — Turn.
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Si/n. Fur. j,. 307, Hist. FUC. t. 107.
F, repens, lAghtf.— I Ira articulataj C. Buds.
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F. cispitosus. Star/di.—
Frequent on the rock} ihorea of Great Britain, y. — From half an
inch to an inch or more in length, densely matted, remarkably catenu-
luted with the coii.-tru tin-.
Tribe XI. Ulv \< i
I 'hints found in tin 000, in f'r, sli -watt r OT OH da nip CTOU ml '. Sr..