Fohjsrphonia. Ruudomele^. - 10 M 



81. P. GuERNiSACi (Crouan. in Ann. Sc. Naf. 1849 font. 10. p. 

 373) decomposito-dichotoma subfastigiata ramulisque inter- 

 mixtis obsita, usque in ramulos corticata, ramulis patentis- 

 simis multo tenuioribus abbreviatis decomposito-dichotomis 

 fastigiatis, articulis vix conspiciendis diametro brevioribus, 

 sphivrosporis in ramulis fastigiatis verrucoso-distortis, ke- 

 ramidiis .... 



Grammitella Gueniisaci Crounn. 1. c. tab. 12 CH 

 Exsicc. Crouan Alg. Finist. n:o 317 ! 



Hab. in rupibus demersis oceani atlantici prope Brest 

 (Crouan!). 



A radico scutata frons surgit 4 - (i-pollicaris, crassitie peima" co- 

 lumbina^, apicibus tantum atteniiatis, deliquescente-dichotoma. subfasti- 

 giata, nuda aut ramulis minutis obsita. Rami plus minus distantes et 

 elongati, sa'pe incurvi, terminales a basi latiore longe attenuati. Ra- 

 muli in planta juvenili nulli, in fructifera provenieutes, frondi multi- 

 plo tenuiores, lineani vix longi, subverticaliter a fronde exeuntes, di- 

 chotomo-decompositi fastigiati, ramellis erecto-patentibus a basi latiore 

 attenuatis articulatis, articulis diametro brevioribus-, spha;rosporfc in 

 his verrucoso-distortis evolvuntur, in singulis articulis singula, longi- 

 tndinaliter seriata;, bic illic uni-lateraliter prominuIa\ Keramidia mihi 

 ignota. Articuli nusquam nisi in ramulis conspiciendi, exsiccatione 

 hic illic observandi, diametro breviores', superficies planta^ cellulis 

 hexagonis reticulata. Substantia carnosa. 



Species nullo negotio a proximis dignoscenda, ramificatione dicho- 

 toma et ramulis minutis dichotomo-fastigiatis. P. hirta, qua? ramifica- 

 tione convenit, ramulis simpliciusculis dignoscatur. P. Derbesii et 

 raniificatione et ramulis simpliciusculis^ P. subcontinua ramificatione 

 et ramulis multo majoribus diiferunt. 



Planta a Cel. Crouan eximie illustrata, sed generis novi typus 

 considerata fuit, quod quomodo a Rytiphlaa et Rhodomela distaret 

 bene exhibuerunt, a Polysiphonia vero uon item. Fronde tota con- 

 tiiina a plurimis Polysiphoniis distat, cnm speciebus vero aliis corti- 

 catis omnino, si quid video, convenit. Nisi itaque omnes corticatas, 

 gradn evolutionis corticis ab aliis tantum diversas, in proprinm genus 

 invila natura referas, P. Guernisaci a cateris divellere non liceat. 



82. P. Derbesii (Solier mscr.) fuscescens decomposito-pinnatim 



ramosa ramulisque intermixtis obsita, usque in ramos su- 

 periores corticata, ramulis patentissimis multo tenuioribus 

 abbreviatis simpliciusculis a basi longe attenuatis, juvenili- 

 bus penicillatis, adultis rigidiusculis, articulis diametro sub- 

 IV. • 67 



