Ser. RHopOSPERME. Fam. Ceramiec. 
Prate LXVII. | 
GRIFFITHSIA EQUISETIFOLIA, 4. 
Gen. Cuar. Frond rose-red, filamentous; filaments jointed throughout, 
mostly dichotomous; ramuli single tubed; dissepiments hyaline. 
Fructification of two kinds, on distinct individuals; 1, ¢etraspores 
affixed to whorled involucral ramuli; 2, gelatinous receptacles (favella) 
surrounded by an involucre, and containing a mass of minute angular 
spores. GRIFFITHSIA,—so named by Agardh, in honour of Mrs. 
Griffiths, the most distinguished of British Algologists. 
GrirriTusta equisetifolia; stems robust, cartilaginous, whorled throughout 
with closely imbricated, incurved, many times dichotomous ramuli. 
GRIFFITHSIA equisetifolia, 4g. Syn. p. 28. Hook. Fl. Scot. part 2. p. 84. 
Ag. Syst. p. 143. Grev. Fl. Edin. p. 312. Ag. Sp. Alg. vol. ii. p. 133. 
Hook. Brit. Fl. vol. i. p. 337. Wyatt, Alg. Danm. no. 181. J. Alg. 
Medit. p.78. Harv. in Mack. Fl, Hid. part 3. p.211. Endl. 3rd Suppl. 
p- 35. 
Haxvrvs equisetifolius, Kitz. Phyc. Gen. p. 374. 
ConFERVA equisetifolia, Lightf. Fl. Scot. p. 984. With. vol. iv. p. 133. 
Dillw. Conf. t.54. E. Bot.t.1479. Esper. Fuc. Sup. t. 4. 
ConFERVA imbricata, Huds. Fl. Ang. p.603. Roth. Cat. vol. ii. p. 281. 
ConFERVA cancellata, Roth. Cat. vol. i. p. 230. 
CERAMIUM equisetifolium, D.C. Syn. p. 8. 
Has. On marine rocks, at extreme low water mark. Perennial. Summer. 
Frequent on the southern and western shores of England, and Ireland. 
Wales, common, Mr. Ra/fs. Rare in Scotland. Fnth of Forth, 
Mr. Yalden (Iightf.). Jersey, Miss White and Miss Turner. 
Geoer. Distr. Atlantic shores of Europe. Mediterranean Sea. Falkland 
Islands, Agardh. 
Descr. Root, an expanded callus, coated with shaggy fibres. Stems, mostly 
solitary, from three to nine inches in height, and from a quarter-line to 
nearly a line in diameter, much and irregularly branched, and elothed 
throughout with short ramuli, which on the older parts of the fronds are 
densely aggregated, forming an irregular shaggy pile, but on the younger 
parts they are regularly whorled, the apices of the lower whorls lying closely 
over the bases of those above them. Main branches long, either subsimple 
or once or twice irregularly forked, or repeatedly dichotomous, generally 
furnished with numerous short, spindle-shaped, simple branchlets, given off 
laterally, and at very uncertain distances, sometimes scattered along the 
branches, sometimes crowded round the apices. These are clothed throughout 
with whorled, dichotomous, incurved ramuli. Joints of the branches about 
twice as long as broad ; of the ramuli, 3—4 times, swollen upwards. Farelle 
borne on the tips of short branches, imperfectly involucrate, two or three _ 
s 
