Ser. GONGYLOSrERMEJ;. (95) Fam. CERAMIACEiE. 



Plate CI. 

 CERAMIUM DESLONGCHAMPII.— C/?aw. 



Gen. Char. — Frond filiform, single tulied, articulated ; joints, and occasionally more or 

 less of the articulation, pervaded by coloured cells. Fructification of two kinds, on 

 distinct plants : 1. Favellas, roundish, with a pellucid limbus, and generally sur- 

 rounded at the base by an involucre of few short articulated spine-like ramuli ; 

 2. Tetraspores, more or less immersed in the ultimate ramuli. Name from 

 Kepanos, ' ' a pitcher ; " but the name is not applicable to the fruit of any species 

 of the genus as now restricted. 



Ceramium Deslongchampii — Frond filiform, cylindrical, attenuated at 

 the summit, much branched in a very irregularly dichotomous manner, 

 the apices mostly forked, straight, acuminate ; articulations two to three 

 times longer than broad in the main stems, very short upwards, those of 

 the apices scarcely apparent. Favellee lateral on the upper ramuli, with 

 one to tlu'ee involucral spines ; tetraspores scarcely immersed, forming a 

 ring roimd the dissepiment. 



Ceramium Dedongchamiyii . — Chauv. hiAlg. Norm. ; J, Ag. Advers. p. 26; Wyatt, 

 Alg. Damn. No. 218 ; Hook, et Harv. in Lond. Journ. Bot. vol. vi. 

 p. 410; Harv. P. B. plate 219 ; Harv. Man. p. 162; Harv. Syn. 

 p. 132; Atlas, plate 52, fig. 236; /. G. Agardh, Sp. Gen. Alg. 

 vol. ii. p. 122. 



Ceramium Agardhianum. — Griff, in Harv. Man. 1st ed. p. 99. 



GoNGKOCERAS DeslongcJiampU. — Kutz. in Linn. xv. p. 735 ; Phyc. Gen. p. 379, 

 t. 46, fig. 1. 



Hab. — On stones, shells, rocks and smaller Algse, generally between tide-marks. 

 Annual. Spring, summer, and early autumn. Not uncommon around aU the British 

 coasts. 



Geogr. Dist. — Coasts of France, Heligoland {Binder) ; Tasmania {Gunn.). 



Description. — Root, a minute disc, with frequently long transparent 

 jointed fibres. Fronds densely tufted, two to four inches long, and about 

 one-eighth of a line in diameter, much branched in a very iiTegular 

 manner, sometimes dichotomous, more frequently secund, occasionally 

 subpinnate ; main branches cylinchical, ramuli acuminate, simple or 

 forked, scarcely incurved ; articulations at the base about half as long 

 as broad, about the middle two to three times longer than broad, but 

 rather irregular, shorter upwards until lost in the apices ; dissepiments 

 and intemodes equal, the latter often suffused with a deep but trans- 



