Ser. OONGYLOSPEEME/E. ( 99 ) Fam. CERAMIACE^. 



Plate CIL 

 CEEAMIUM DIAPHANUM.— i^o^'A. 



Gkx. 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. Favellaj, 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 

 KfpafjLos, "a pitcher ;" but the name is not applicable to the fruit of auy species 

 of the genus as now restricted. 



Ceramium diaphmiicm. — Frond rather stout, gradually attenuated 

 towards the summit ; main divisions mostly dichotomous, more or less 

 beset with short, simj^le or dichotomously multifid ramuli ; articulations 

 of the main divisions three to four times as long as broad, of the ramuli 

 much shorter than broad ; favella) terminal or lateral on the ramuli, 

 iuvolucrate; tetraspores immersed in the shallow joints. 



Cerahiiuji diaphanum. — EotJi, Oaf. Bot. vol. iii. p. 154 ; Ag. Syn. p. 61 ; Eooh. 

 Fl. Scot, part 2, p. 85 ; Ac/. Syst. p. 133 ; Ag. Sp. Alg. vol. ii. 

 p. 150; Grev. Fl. Edin. p. 310; WtjciU, Alg. Damn. No. 87; 

 /. Ag. Alg. Medlt. p. 81 ; Endl. 3rd Suppl. p. 27 ; Harv. in Hooh. 

 Br. Fl. vol. ii. p. 336 ; Harv. in Mach. Fl. Hih. part 3, p. 210 ; 

 Harv. P. B. plate 193; Haw. Man. p. 163; Harv. Syn. p. 132; 

 Atlas, plate 52, fig. 237; Harv. N. B. A. part 2, p. 215; /. G. 

 Agardh, Sp. Gen. Alg. vol. ii. p. 125. 



HoRMOCERAS diuphanum. — Kiitz. Phyc. Gen. p. 378; KUtz. in Linn. vol. xv. p. 733. 



Conferva diapliana. — Lightf. Fl. Scot. p. 996 ; Fl. Ban. t. 951 ; Roth, Fl. Germ. 

 p. 525, and Cat. vol. ii, p. 226 ; Billw. Conf. t. 38 ; E. Bot. t. 1742 ; 

 WitJi. vol. iv. p. 139. 



Conferva nodulosa, — Huds. Fl. Angl. p. 600. 



Bortna diaphana. — Grat. Bid. Class, t. 11 ; Bory, Moree, p. 77, No, 1797. 



Hab. — Parasitical on the smaller Algae in rock-pools between tide-marks. Annual. 

 Summer. Not uncommon around all the British coasts. 



Geogr. Dist. — Temperate; Atlantic and Pacific Oceans; Mediterranean and Black 

 Seas {Ag.). 



Description. — Root, a minute conical disc. Fronds much branched 

 from near the base, three to six inches long, one-sixth of a line thick 

 in the middle, attenuated at the base and at the points ; main divisions 

 mostly dichotomous, at length more or less in^egular by means of the 

 innovations, beset throughout with short, simple, forked or dichotomously 



