Ser. Rhodosperme^. Fam. Rhodomelacece. 



Plate CLV. 



POLYSIPHONIA SPINOSISSIMA, Haw. 



Gen. Char. Frond filiform, partially or generally articulate ; the joints lon- 

 gitudinally striate, composed of numerous cylindrical cells surrounding 

 a central cell (sometimes coated with one or several rows of smaller 

 cells). Fructification: 1, ovate or urceolate ceramidia, containing 

 a tuft of pear-shaped spores; 2, tetrasjwres, immersed in swollen 

 branches. — Polysiphonia {Grev.), from iroXv^, many, and ai^wv, 

 a tube. 



Jrons fill for mis, plus minus articulata ; articulis longitudinaliter pluristriatis, 

 ex celluUs 4-20 cylindraceis cellidam centralem cingentibus formatis (nunc 

 ceUidis minoribus pluriseriatis corticatlsj. Fruct. : 1^ ceramidia ; 'i, tetra- 

 sporce in ramulis ultitnis uniseriatce. 



Polysiphonia spinosissima ; brownish, densely tufted ; frond setaceous, 

 shrubby, articulate throughout, furrowed, decompoundly much 

 branched ; branches directed every way, close together, patent, vir- 

 gate, several times pinnately decompound ; ramuli spine-like, squar- 

 rose, spirally inserted, very short and close together ; articulations 

 7 -tubed, those of the branches once and half as long as broad, those 

 of the ramuli very short. 



P. spinosissima ; /«5ce5ee«5, de7ise ccespitosa, fronde setacea fruticosa articulata 

 sulcata decomposite ramosissima ; ramis quaquaversis creberrimis patentibus 

 ■pluries pinnatim composUis ; raiimlis splncpformibus squarrosis spiraliter in- 

 sertls brevibus crebrls ; articulis septemsipJioniis, ramorum diametro sesquilou- 

 ffioribus, ramulorum brevissimis. 



Polysiphonia spinosissima, Harv. Alg. Austr. Ex,sic. n. 173. Harv. in Hook. 

 Ft. Tasm. v. 2.j9. 301. 



Hab. In a salt-water creek near "Belfast,^' Port Fairy, JF. H. H. Tas- 

 mania, C. Stuart. 

 Geogr. Distr. South coasts of Australia. Tasmania. 



Descr. Pronds densely tufted, 2-3 inches high, pellucidly articulate throughout, 

 alternately branched, shrubby. Branches virgate, subsimple, very densely 

 set throughout, as well as the stem, with short, patent ramuli directed to 

 every side. Ramuli spine-like, 2-3 lines long, closely crowded, when young- 

 simple and slenderly subulate, afterwards set with smaller secondary subu- 

 late ramuli : all tipped with hair-like fibres. Articulations 7-tubed, rather 

 shorter than their breadth, with wide hyaline spaces between the tubes, 

 and broad hyaline dissepiments. Fruit unknown. Colour brownish, with 



