Ser. RHoDOSPERME. Fam. Ceramiea. 
Puate CCLV. 
CERAMIUM FASTIGIATUM, dav. 
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. ruectification of two kinds on 
distinct individuals; 1, ¢e¢raspores either immersed in the ramuli or 
more or less external ; 2, sessile, roundish receptacles (favella) having 
a pellucid limbus, containing minute, angular spores, and subtended 
by one or more short, involucral ramuli. Crramium (Roth),—from 
kepanos, a pitcher; but the fruit is vot pitcher-shaped. 
Crramium fastigiatum; frond capillary, of equal diameter throughout, 
flaccid, dichotomous, level-topped; the axils acute ; articulations pel- 
lucid, those of the middle of the stem from four to six times longer 
than broad, the upper gradually shorter, and coloured; dissepiments 
coated with coloured cells; favellee small, subterminal, subtended by 
three or four involucral ramuli. 
Crramivm fastigiatum, Harv. in Hook. Lond. Journ. Bot. vol.i. p. 303. 
Wyatt, Alg. Danm. no. 86. Harv. Man. 1st ed. p. 99. 
GoneroceRas fastigiatum, Ky. in Linn. xv. p. 736. Phyc. Gen. 
Has. On rocks, &c., near low-water mark; rare. Annual. Autumn and 
winter. Torquay, Mrs. Griffiths. Mt. Batten, Plymouth, Rev. IV. 
S. Hore. Frith of Forth, Dr. Greville. 
Grocer. Distr. Mediterranean Sea, Kiitzing. Hast coast of North America. 
Dezscr. Filaments 4-5 inches high, as thick as human hair, densely tufted, of 
equal diameter throughout, fastigiate, many times dichotomous, regularly 
forking from the base to the apex, mostly bare of lateral branchlets, but 
sometimes having a few, short, simple or forked ramuli. The lower axils 
distant, and somewhat spreading; the upper close together and narrow, 
acute. Apices generally emarginate, the points straight, or slightly curved, 
somewhat hooked, but not rolled inwards. Lower articulations from three 
to six times as long as broad, pellucid and colourless, furnished occasionally 
with a few scattered granules; upper articulations gradually shorter, the 
pellucid spaces suffused with pale, watery endochrome ; the uppermost very 
short and strongly coloured. Favelle of small size, sessile near the apex 
of the frond, having a few short, involucral ramuli. TZeéraspores I have not 
seen. Substance tender, and flaccid, closely adhering to paper. Colour, in 
the tuft, a dark purple, fading in the herbarium to brick-dust colour; in the 
filament, a clear purplish lake. 
This is one of the rarest and most beautiful of the British 
species of Ceramium. It is nearly related to C. nodosum, parti- 
cularly in ramification, and in the diameter of its filaments; but 
VOL. III. F 
