216 ALQM RHODOSPERMEjE. [Callithamnion. 



# * Plumules dense, lanceolate or narrow '-oblong ', bipinnate. 



11. C. gracillimum, Ag. Graceful Callithamnion. Fila- 

 ments capillary, decomposito-pinnate, distichous; upper plu- 

 mules long, narrow-ovate or sublanceolate, patent, bi-tripinnate ; 

 main articulations cylindrical, 3 4 times, those of the pinnae 

 2 8 times longer than broad ; capsules terminal on the pin- 

 nules. Harv. in Hook. Br. PI. v. ii. p. 345. 



Very rare. Black Castle, Wicklow ; W. H. Harvey. Filaments 

 1 4 inches high, distichously branched, many times pinnate ; the out- 

 line of the principal branches broadly ovate, and resembling most deli- 

 cate ferns in miniature. Colour rose-red. 



2. Secondary or smaller branches alternately dichotomous. Cap- 

 sules elliptical, solitary, mostly axillary ; favellce binate. 



12. C. corymbosum, Ag. Corymbose Callithamnion. Capil- 

 lary, flaccid, gelatinous, entangled ; secondary branches alter- 

 nate, excessively dichotomous, subflabellate, level-topped ; ulti- 

 mate dichotomies acute, appressed; articulations of branches 

 8 10, of the ramuli 5 6 times longer than broad. Harv. in 

 Hook. Br. Fl v. ii. p. 346. Conf. corymbosa, E. Bot. t. 2352. 

 (joints too short.) Cal. byssoideum, Am. MS. Harv. I. c. 

 p. 342. 



Rare. Bantry bay ; Miss Hutchins. South Bull, Dublin ; W. H- 

 Harvey. 1 3* inches high, excessively delicate and tender, much 

 branched, secondary branches byssoid, rose-red. I have been favoured 

 with an extensive series of this variable plant by my kind friends, Mrs. 

 Griffiths and Miss Cutler ; and now fully agree with these acute bota- 

 nists in considering the C. byssoideum of the Br. FL only as a va- 

 riety, whose peculiar characters probably depend on age. The posi- 

 tion of the capsules, which I had hoped constant, is very variable ; and 

 they are often lateral and axillary in the same individual. 



13. C. versicolor, Ag. Changeable Callithamnion. Fila- 

 ments setaceous at base, capillary above, distichously branched 

 in a pinnate manner ; penultinate branches naked below, dicho- 

 tomous above, level-topped ; ultimate dichotomies spreading ; 

 main articulations 4 6, those of the ramuli 2 3 times longer 

 than broad; capsules solitary, axillary. Harv. in Hook. Br. 

 Fl. v. ii. p. 346. p. seirospermum ; ultimate ramuli monili- 

 form ; joints globular, inclosing a dark red mass. Wyatt. Alg. 

 Danm. No. 91. 



Very rare. South Bull, Dublin, (a single specimen) ; W. H.Harvey. 

 3 4 inches high, as thick as hog's bristle at base, distichously branched, 

 of a fine rose-red colour. A larger and coarser plant than C. corym- 

 bosum, the branches pinnate and naked at base. 0. is a very remark- 

 able variety discovered at Torquay by Mrs. Griffiths, in which the 

 ultimate ramuli seem resolved into chain-like strings of capsules ; each 

 joint having the appearance and structure of a capsule. This variety 



