Sek. GONGYLOSPERMEiE. ( 11 ) Fam. RHODYMENIACEJ;. 



Plate LXX. 

 RHODYIMENIA VAJ.UAT A.— GreiJ. 



Gen. Char. — Fronds flat, subcoriaceous, cellular, without veins or midrib. Fnictification 

 of two kinds, on distinct plants : 1. Convex tubercles (coccidia), containing a 

 mass of minute spores attached by a central placenta ; 2. Tetraspores, cruciate, 

 imbedded in cloud-like patches among the surface cells of the frond. Name from 

 poSeos, ' ' red, " and vixriu, ' ' a leaf or membrane." 



Rhodymema palmata. — Fronds tufted, somewhat leathery, irregularly 

 dichotomous ; segments obtuse, frequently fringed more or less with 

 proliferous lacinise ; tetiuspores in roundish sori scattered over the 

 whole frond. 



Rhodymenia palmata. — Grev. Alg. Brit. p. 93 ; Hooh. Br. Fl. vol. ii. p. 291 

 Wyatt, Alg. Damn. No. 110 ; Harv. in Mach. Fl. Hih. part 3, p. 195 

 Harv. P. B. plate 217; Harv. Man. p. 127; Harv. Syn. p. 107 

 Atlas, plate 41, figs. 189, 190 ; Harv. N. B. A. part 2, p. 148 ; /. G. 

 Agardh, Sp. Gen. Alg. vol. ii. p. 376. 



Sph^rococcus palmatus. — Kiltz. Phyc. Gen. p. 409, t. 63, f. 1. 



Halymenia palmata. — Ag. Syn. p. 55 ; Ag. Sp. Alg. vol. i. p. 204 ; Ag. Syst. 

 p. 242 ; Spreng. Syst. Veg. vol. iv. p. 333 ; Hook. Fl. Scot, part 2, 

 p. 107 ; Post, ft Hupp. p. 18. 



Delessekia palmata. — Lamour. Ess. p. 37. 



Ulva palmata. — Dec. Fl. Fr. vol. ii. p. 12 ; With. vol. iv. p. 123 ; Lyngh. Hyd. 

 Dan. p. 24 ; Grev. Fl. Edin. p. 298. 



Focus palmattis. — Linn. Sp. PI. p. 1630 ; Huds. Fl. Angl. p. 579 ; LigUf. Fl. 

 Scot. p. 933, t. 27 ; Good, d; Woodw. Linn. Trans, vol. iii. p. 163 ; 

 Gunn. Fl. Norv. vol. ii. p. 69; Turn. Syn. p. 175; Turn. Hist. 

 t. 115 ; E. Bot. t. 1306 ; Hook, in Fl. Lond. new series, with a 

 figure. 



Fucus ovinus. — Gunn. Fl. Norv. vol. i. p. 96 ; Mohr, Hist. Isl. p. 245. 



Fucus caprinus. — Fl. Dan. t. 1128 ; Esper, Ic. p. 146, t. 74. 



FtTOUS hullatus. — Fl. Dan. t. 770. 



Fucus rubens. — Esper, Ic. t. 75. 



Fucus dulcis. — Gmel. Hist. p. 1S9, t. 26 (fide Turner). 



Hab. — In the sea on rocks, on old shells, and on the stems oi Laminar ice. Common 

 all round the British coasts. Biennial. Winter, spring, and early summer. 



Geogr. Dist. — Atlantic shores of Europe ; Iceland. 



Description. — Root, a short flattened disc. Fronds much tufted, 



