191 AhGM RHODOSPERMEjE. [Ehmhmenia 



— Name ; poco%; red, and vfiyv, a membrane. This genus is 

 distinguished from Nitophylliim, by the denser substance of 

 the frond, and the general distribution of its granules through 

 the whole, or irregular portions of the membrane. 



1. R. bifida, Grev. Bifid Rhodomenia. Frond membrana- 

 ceous, tender, thin, dichotomously divided from the base, seg- 

 ments broadly linear ; apices subcuneate, bifid, obtuse ; cap- 

 sules chiefly confined to the margin. Hook. Br. FL v. ii. p. 289. 

 E. Bot. t. 773. 



On rocks, &c. ; rare. Belfast ; Mr. Templeton. Bantry bay ; Miss 

 Hutchins. Miltown Malbay, Kilkee and Wicklow ; W. H. Harvey. 

 I — 3 inches high, thin and delicate, fine rose-red. Mr. Turner's variety 

 (3. (which I have not found in Ireland) differs so much from the usual 

 form, that it might easily be mistaken for a different species. It is of a 

 darker colour, with exceedingly narrow segments, which are much 

 lacerated and entangled. 



2. R. laciniata, Grev. Laciniated Rhodomenia. Frond 

 thickish, subcartilaginous, more or less palmate or flabelliform, 

 cleft into numerous broad, wedge-shaped segments, which are 

 again divided in a subdichotomous manner ; apices obtuse ; 

 margin in fructification fringed with minute laciniae, in which 

 the capsules are imbedded. Hook. Br. FL v. ii. p. 289. Turn. 

 Hist. t. 69. E. Bot. t. 1068. 



Sea-shores, common. I have received superb specimens from Lame, 

 near Belfast, through the kindness of Dr. Drummond, A fine species, 

 6 — 10 inches long, of a bright crimson colour. 



3. R. Palmetta, Grev. Fern-shaped Rhodomenia. Stem 

 short, cylindrical, quickly expanding into a roundish flabelli- 

 form frond, which is more or less cleft in a dichotomous manner, 

 segments cuneate ; axils rounded ; apices (according to the state 

 of fructification) either erose or rounded, obtuse; capsules 

 mostly terminal ; granules in the expanded apices. Hook. Br. 

 FL v. ii. p. 290— F. Palmetta. Turn. t. 73. E. Bot. t. 1120. 



On rocks, or (more generally) on the stems of Laminaria digitata. 

 Fronds tufted, about 3 inches high, very variable in the length of the 

 stipes ; tolerably constant in its other characters. Substance cartila- 

 ginous. Colour, a full rose-red. Hoot accompanied by creeping fibres. 



4. R. ciliata, Grev. Ciliated Rhodomenia. Frond thick, 

 subcartilaginous, rising from a short stipes, lanceolate, ir- 

 regularly pinnated, with lanceolate or cleft segments, atte- 

 nuated at base ; margin (and often the disk) furnished with 

 simple, subulate ciliae, which bear the capsules at their extre- 

 mities; granules in the disk; root fibrous, creeping. Hook. Br. 

 FL v. ii. p. 291.— Fucus ciliatus. E. Bot. t. 1069. 



On rocky shores, not uncommon. 4 — 8 inches high, of a thick sub- 

 stance, and full red colour, which becomes much darker in drying. 



5. R. jitbata, Grev. Cirrhose Rhodomenia. Frond thickish, 

 flaccid, subcartilaginous, linear-lanceolate, much attenuate, 



