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Ser. RHoposPERME®. Fam. Ceramiea. 
Pirate CCLXXVI. 
CERAMIUM DECURRENS, Zitz. 
Gen. Cuar. Frond filiform, one-tubed, articulated; the dissepiments 
coated with a stratum of coloured cellules, which sometimes extend 
over the surface of the articulation. Fructification of two kinds, on 
distinct individuals : 1, ée¢raspores either immersed in the ramuli or 
more or less external; 2, sessile, roundish receptacles (favelle) having 
a pellucid limbus, containing minute, angular spores, and subtended 
by one or more short, involucral ramuli. Crramium (Roth),—from 
kepapos, a pitcher ; but the fruit is zo¢ pitcher-shaped. 
Ceramium decurrens; frond robust, gradually attenuated upwards, dicho- 
tomous, with few lateral branchlets, the apices hooked mwards ; arti- 
culations partially coated with coloured cellules, which extend from 
the dissepiment at each end, but leave a colourless, pellucid space in 
the centre of the articulation ; lowermost articulations twice as long 
as broad, upper very short. 
Crramivum decurrens. Harv. Man. ed. 2. p. 162. 
Hormoceras decurrens (8. majus), Kitz. in Linn. vol.xv. p. 733. Kiitz. 
Phyc. Gen. p.379. Sp. Alg. p. 675. 
Has. On the smaller Alge in tide-pools. Rare? Annual. August. 
On the Harbrich, at Torquay, Mrs. Griffiths (1844). 
Gerocr. Distr. Mediterranean Sea. 
Descr. Frond (in British specimens) six to eight inches long, as thick as hog’s 
bristle below, gradually attenuated upwards, and capillary above, repeatedly 
and pretty regularly dichotomous, but scarcely fastigiate ; the lower divisions 
of the frond distant, the upper more and more approximating. A few simple 
or forked short ramuli are scattered here and there along the branches. 
Articulations in the lower part of the frond about twice as long as broad, 
their upper and lower parts covered with coloured cellules, disposed in 
longitudinal lines ; their middle colourless and bare. In the upper divisions 
of the frond and in the ramuli the articulations are very short, coated with 
cells except a narrow central pellucid band. The apices are strongly hooked 
inwards. I have not seen any fructification. Colour a full red, something 
like the colour of brick-dust, with a slightly purplish hue. Sudstance mem- 
branaceous, uot very closely adhering to paper. 
The original C. decurrens of Kiitzing is described as being 
“minute, scarcely an inch long, and capillary :”°—the plant here 
figured is considered by that author, to whom I transmitted a 
specimen, to be a larger variety of the species, agreeing in all 
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