Scr. Ehodosfkume^. Fam. Wiodymeniacea. 



Plate CLVII. 



RHODYMENIA POLYMORPHA, Haw, 



Gen. Char, i^yo;;^/ flat^ membranous, dichotomous or palmate, composed 

 of two strata of cells ; the medullary stratum of oblong, polygonal, 

 larger cells; the cortical of minute, vertically seriated cellules. 

 Ffuclification : 1, sessile, hemispherical, thick-walled conceptacles, at 

 length opening by a terminal pore, containing densely-packed, spori- 

 ferous filaments issuing from a basal placenta, and surrounded by a 

 gelatinous pellicle; 2, cruciate or tripartite ietrasjjores, either scattered 

 over the frond, collected in sori, or immersed in terminal, shield-like 

 iiemathecia. — Ehodymenia [Grev.], from poZeo<i, red, and vimt]v, a 

 membrane. 



Frons plana, memhranacea, dicJiotoma v. palmata, stratis duohus composita ; 

 straio viedullarl ex cellidis mujiiscidls oblongis polyhedrk, corticali cellidis 

 minimis coloratis pluriserialibus covflato. Fruct. : 1, cystocarpia sessilia, 

 heiidspharica, intra pericarpium crassum demum carpostomio aperlum fila 

 sporifera densissime ar/greyata, e placenta basali emissa, pellicula ydatinoHu- 

 cellulosd velata foventia ; 2, tetrasporce cruciatim v. triatigule divistE, nunc 

 sparsce, nunc in soros subdejinitos collectce v. in netnatheciis terminalibus im- 

 niersce. 



Ehodymenia polymorpha ; stipes short, very soon expanding into the base 

 of the frond ; frond dull red or pale-purplish, very broad, oblong or 

 ovate, polymorphous, sometimes simple, with the margin leaf-bearing, 

 sometimes cleft into numerous lanceolate segments ; segments either 

 simple or variously cleft, or producing marginal leaves; cystocarps 

 very numerous, scattered over the whole frond. 



E. polymorpha ; stipite brevi mox in basifrondis explanato ; fronde dilute ridjra 

 latissima oblongo-ovata polymorpha nunc subsimpUci maryine foliifera, nunc 

 in lacinias plures lanceolatas Jissa ; laciniis nunc simplicibus nunc maryine fo- 

 liiferis v. varie inciso-partitis ; cydocarpiis uumerosisshnis per totam frondem 

 dispersis. 



Rhodymenia polyraorpha, Harv. Aly. Austr. Exsic. n. 383 ; Haro. in Hook, 

 fit. Fl.Tasni. t\ 2. p. 319. 



Hab. Thrown up from deep water. Port Fairy, Port Phillip Heads, and 

 Philip Island, Western Port, IF. H. E. Georgetown, Tasmania, 

 W. H. H. 



Geogr. Djstr. Southern coasts of New Holland. Bass's Straits, both sides. 



Descr. Root a small disc. Stem couipressed, cartilaginous, \-^ inches long, cu- 

 neate upwards and gradually expanding into the ba&e of the frond. Frond 



