r h / L c c . u . u .
P l a t e CCXXXI.
CALLITHAMNION POLYSPERMUM, A g .
Gen. C h a r . Frond rosy, or brownisli-red, filamentous ; stem either opake
and cellular, or translucent and jo in ted ; branches jointed, one-tubed,
mostly pinnate (rarely dichotomous or irregular) ; dissepiments hya.-
line. F ru it of two kinds on distinct plants ; 1, external tetraspores,
scattered along th e ultimate branchlets, or borne on little pedicels ;
3, roundish or lobed, berry-like receptacles {fa v e lla ), seated on the
main branches, and containing numerous, angular spores. C a l l i t
h a m n i o n {Lyn g h ),— from koKos, heautiful, and ôagvmv, a little shrub.
C a l l it h a m n io n polyspermum ; tufts globose ; filaments slender, delicate,
loosely much-branched, irregularly divided below-, distichously plumulate
above; plumules long and narrow, simply pinnate ; phmæ
short, simple, patent, acute, spine-like ; articulations of the branches
with a very narrow coloured tube, four or five times as long as
broad, of the ramuli short ; tetraspores globose, hning the inner face
of the pinnæ.
Callithamnion polyspermum, Ag. Sp. Alg. vol. ii. p. 169. Ilarv. in Hook.
Br. Fl. vol. ii. p. 842. Harv. in Mack. Fl. Hib. part 3. p. 214. Harv.
Man. p. 108. Wyatt, Alg. Banm. no. 140. Fndl. 3rd Suppl. p. 34.
Callithamnion Grevillii, Harv. in Hook. Br. Fl. vol. ii. p. 345. Harv.
Man. p. 110. Harv. in Mack. Fl. Hib. part 3. p. 215.
Callithamnion roseum, Grev. Fl. Fdin. p. 311 {not o f Br. Fl.)
Callithamnion purpurascens, Berw. Fl. vol. i. p. 240.
P hlebothamnium polyspermum, Xiifo. Phyc. Gen. p. 374.
H a b . On various Algæ between tide-marks, frequently on Fucus v
and F. serratus. Annual. Summer. All round the coast.
Geogr. Distr. Atlantic shores of Europe.
Desck. Boot discoid, smaU. Tufts globose, one to three inches in diameter,
dense. Filaments capillary, excessively branched ; stem zigzag, with short
articulations, traversed by a few fibres but not thereby rendered opake,
irregularly divided, and either somewhat bare or well furnished with alternate,
secondary branches. Branches long and slender, zigzag, hearing a
second or third series, the latter alternately plumulate with considerable
regularity. Plumules usually long and narrow, simply pinnate, or occasionally
the upper part more compound. Pinnæ usually short, patent, subulate,
sometimes recurved, in luxuriant specimens so far lengthened that the outline
of the plumule becomes ovate. Articulations of the branches 4 -5 times
as long as broad, witb a very narrow bag of endochrome ; of the ramuli
twice as long as broad, fuUy coloured. Tetraspores usually lining the inner
faces of the pinnæ, globose. Favelloe of large size, in dense clusters,
bursting from the rachis of a distorted plumule. Occasionally the place of
tetraspores is occupied by round bodies (antheridia ? or rather viviparous
tetraspores) formed of innumerable minute cells, strung together. Colour,
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