RHUDOMELEiE. 787 



Ordo XVI. RHODOIHELE^. 



Rhodomelese J. Ag. Symh. in Linnma XV. p. 23. Alg. nied. p. 

 116. Endl. G-en. Pl. Suppl. III, p. 44. Harv. Ner. austr. p, 

 9. Ner. Bor. Amer. p. 9. Zanard. Pl. niar. ruhr. p. 47. 

 Monf. Syll p. 416 (excl. gener.) ; Rytiphlese, Polyphacese, 

 ThamnophoreEe, Heterocladieee, Anomalophyllese et Cera- 

 mieee (quoad partes) Decsne Class. p. 62 sc^u.; Dasyese, 

 Polysiphoniese Chondrieee, Amansiee, Rytiphleacese, Car- 

 poblepharidefe, Claudiea? (quoad partes) Kiitz. Fhyc et 

 Sp. Alg. 



Frons articulata monosiphonia, sfepissime polysiphonia aut areo- 

 lato-zonata, cellulis pericentralibus e regione positis, nuda 

 aut externe celhilis minoribus angulatis corticata. Cysto- 

 carpia externa, pericarpio celluloso munita, carpostomio 

 regulari aperta; fila gemmidiifera invicem libera, a pla- 

 centa basali radiantia, in articulo terminali clavato trans- 

 formato gemmidia pyriformia foventia. Sph(JBrospor(B in cel- 

 lulis pericentralibus evolutfe, certo ordine seriatse. 



Algse coccinefe aut purpurascentes, exsiccatione ut pluri- 

 mum atropurpurea? aut nigricantes, nunc leetiorem servantes 

 eolorem aut facilius decoloratse et albescentes. Frondes forma 

 varise; inferiores filiformes teretiusculee aut leviter compressee, 

 fere totee conformes (Polysiphonia, Tsenioma, Alsidium, Bos- 

 trychia, Chondriopsis, Rytiphlfea, Rhodomela), aut ramulis a caule 

 evidentius distinctis (Digenea, Trigenea, Bryothamnion) instructee, 

 paulo superiores complanatee evadunt, costam propriam et la- 

 minam separantes, ceeterum conformes (Kiitzingia, Amansia, Dic- 

 tymenia, Vidalia, Lenormandia), aut difformes, ramulos fructi- 

 feros quasi heterogeneos exserentes (Polyphacum, Heterocladia); 



IV. ' 53 



