Ser. GONGYLOSPERME.E. i Til ) Fam. CERAMIACEJE. 



Plate CVL 

 CERAMIUM ECHIONOTUM.— /. Acj. 



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

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

 distinct plants : 1. Favellffi, 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 iiltimate ramuli. Name from 

 Kepa/xos, "a pitcher ;" but the name is not applicable to the fruit of any species 

 of the genus as now restricted. 



Ceramium echionotum. — Fronds cylindrical, of equal diameter 

 throughout, much branched dichotomously ; branches erect, apices forked 

 and involute ; articulations, towards the middle, three to four times 

 longer than broad, gradually shorter iipwards ; dissepiments slightly 

 swollen, beset with scattei'ed, squarrose, pellucid, single-jointed spines ; 

 favellse lateral near the apices of the branches, with several (four to five) 

 incurved involuci'al spines ; tetraspores very prominent, one or two on 

 the outer margin of the ramulus. 



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Ceramium echionotum, — /. Ag. Advers. p. 27; Harv. P. B. plate 141; Rarv. 

 Man. p. 165; Harv. Syn. p. 135; Atlas, plate 52, fig. 239; /. G. 

 Agardh, Sjp. Gen. Alg. vol. ii. p. 131. 



Hab. — On rocks, stones, shells, &c., between tide-marks and in rock-pools, on other 

 Algae. Annual. Summer and autumn. Not uncommon. 



Geogr. Dist. — Atlantic and Mediterranean coasts of Europe. 



Description. — Fronds very densely tufted, slender and cylindrical, 

 three to four or " six " inches long, very much branched ; branches 

 dichotomous, erect, subfastigiate, without lateral branchlets, or with 

 few scattered, simple or forked ramuli, apices forked and incurved. 

 Articulations, below the middle, three to four times longer than broad, 

 gradually shorter upwards, those of the apices very short, pellucid ; 

 dissepiments opaque, slightly swollen, beset with short fusiform, pellucid, 

 scattered, squarrose spines, much attenuated at their base, and single- 

 jointed. Substance somewhat rigid, and not very perfectly adhering to 

 paper. Coloiu-, a more or less deep piu'plish red. Favellae lateral or 

 axillary on the upper ramuli, one or two together, or one- or two-lobed, 

 with four to five strongly incui'ved involucral spines, twice as long as 

 the favellse. Tetraspores mostly solitaiy or rarely two together, very 



