Ser. Riiodospeume;e. Fam. Rhodomelacea. 



Plate XXVIII. 



RIIODOMELA PERICLADOS, Sond. 



Gen. Char. Frond terete, dendroid, inarticulate, solid, coated with minute 

 polygonal cellules ; the axis articulated, polysiphonous. Fructification : 

 1, ovate ceramidia containing a tuft of pear-shaped spores; 2, tetra- 

 spores lodged in swollen ramuli or in pod-like stichidia, in a single 

 or double row. — Rhodomela {Ag.), from poheos, red, and fiekas, 

 blade ; because these plants become darker in drying. 



Frons teres, dendroidea, inarticulate/, solida, cellulis minutis pohjgonis corlicala ; 

 fi.ri. articulato polysiphonw. Fruct. : 1, ceramidia ovata, sporas pedicellatas 

 fasciculatas pyriformes foventia ; 2, tetraspores triangule devisee, in ramulis 

 immersa v. in stichidiis propriis evolutce. 



Rhodomela periclados ; fronds tufted, subsimple or forked ; branches 

 few, lateral, simple; ramuli thorn-shaped, acute, short, at length 

 multipartite, inserted on all sides ; ceramidia subglobose, sessile or 

 on short pedicels ; tetraspores lodged in the multifid ultimate ramuli. 



R. periclados, ccespitosa ; fronde subsimplici v. furcata, ramis panels la feral ions 

 simplicibus, ramulis aculeiformibus acutis brevibus d'emum fasciculato-multijidis 

 undique insertis ; ceramidiis subglobosis sessilibus v. brevissime pedicellatis ; 

 tetrasporis in ramulis fascicidatis ultimis uidulantibus. 



Rhodomela periclados, Sond. in Linnaa, v. 26. p. 523. 



Rhodomela simpliciuscula, Harv. Alg. Austr. Exsic. n. 136. 



Hab. On rocks and in rock-pools, near low-water mark. Brighton, Port 

 Phillip, Dr. Ferd. Mueller, W. H. H. In Tasmania : on the east 

 coast and at Brown's River, Mr. Gmm ; South Port, Mr. C. Stuart. 



Geogk. Distr. As above. 



Descr. Boot matted, branching. Fronds many from the same base, 4-5 inches 

 high, either quite simple or once or twice forked, and now and then furnished 

 with two or three lateral branches, filiform, as thick as a hog's bristle, naked 

 below, ramuliferous above. Rumidi about two lines long, setaceous, subulate, 

 inserted on all sides, crowded or scattered, at first quite simple, afterwards 

 often irregularly multifid and somewhat corymbulose. The young ramuli 

 are tipped with a pencil of soft, byssoid, articulated fibres. The frond is 

 perfectly opaque in every part, and of densely cellular substance ; the axis 

 is four-tubed, the cells composing it being of small size. Ceramidia sessile 

 or shortly stalked, borne on the sides of the ramuli. Tetraspores lodged 

 in multifid ramuli, the plants bearing them being always distinguishable 

 from the capsuliferous ones by the greater composition and abundance of 

 their ramuli. Colour a dark brownish-purple, becoming brown or black in 



