Alga.~] FLORA OP NEW ZEALAND. 229 



erectis axillis angustissimis, apicibus acuminatis, articulis infimis striseformibus brevissimis, mediis diame- 

 trum aequantibus, ramulorum majorum diametro brevioribus, minorum brevissimis striaeforinibus, siphonibus 

 quatuor amplis. 



Hab. Dredged in five fathoms, D'Urville Island, JLyall. 



Habit of P. elongata, but very different. Nearest to P. variabilis, but much brighter in colour, with very 

 different articulations, and very acute or acuminate ramuli. Frond 8 inches long, as thick as hog's-bristle, some- 

 what attenuate, the main stem and the branches cartilaginous ; the ramuli very flaccid, and closely adhering to 

 paper ; ultimate ramuli frequently secund. Joints visible in all parts, those toward the base of the stem with sup- 

 plementary cellules. 



7. Polysiphonia amphibia, Harv.; fusco-rubens, csespitosa, fronde articulata capillari rigidiuscula decom- 

 posite ramosissima sensim attenuata, ramis ranxulisque alterne v. secundatim divisis vix dichotomis, minori- 

 bus saepe basi longe nudis apice ramosis, axillis patentibus, articulis bivenosis, mediis nodosis diametro sub- 

 duplo, superioribus duplo triplove, ultimis ssepius sesquilongioribus, siphonibus quatuor, tetrasporis parvis. 



Hab. In a stream of brackish water, covered at high tides by the sea, Massacre Bay, Lyall. 



Tufts dense, 2-3 inches high, intricate. Fronds capillary, much branched, rigid, attenuated upwards, the 

 branches irregularly alternate, many times compounded, the lesser divisions all patent. Ramuli spreading at wide 

 angles, often multifid at the tips. 



Not sufficiently known. It somewhat resembles some states of P. urceolata, but its amphibious locality in- 

 duces us to keep it, for the present at least, distinct. 



8. Polysiphonia rudis, Hook. fil. et Harv., Fl. Ant. v. l.p. 183. t. 74./. 2. Harv. Ner. Amtr.p. 44. 

 Hab. Port Underwood, Cook's Straits, Lyall. (Native of Auckland Islands.) 



9. Polysiphonia implexa, Hook. fil. et Harv. in Lond. J. Sot. v. 4>. p. 538. Harv. Ner. Austr.p. 44. 

 Hab. New Zealand, Eaoul. Cape Kidnapper and Parimahu, Colenso. 



10. Polysiphonia macra, Harv.; dense csespitosa, parva (semimicialis), e fills repentibus orta, caulibus 

 erectis parum ramosis, ramis simplicibus alternis vel secundis filiformibus vix ramulosis, articulis omnibus 

 conformibus trivenosis diametro asqualibus vel sesquilongioribus nunc diametro brevioribus. 



Hab. Akaroa, Lyall. Tidal rocks, Hawke's Bay, Colenso. 



Forming a dense, dark brown mat, on the surface of rocks, the base of the tuft composed of a dense plexus of 

 creeping filaments, which throw up erect, subsimple, or slightly branched, irregularly-divided stems. Not the same 

 as P. implexa ; but not sufficiently known. 



11. Polysiphonia Colensoi, Hook. fil. et. Harv.; caule (unciali-biunciali) setaceo robusto pellucide 

 articulato tetragono quaquaversum ramoso, ramis alterne decompositis ramulisque duplicis generis spiraliter 

 insertis e quoque fere geniculo egredientibus onusto, aliis subulatis simplicibus, aliis pinnatis demum in 

 ramos proficientibus, articulis omnibus diametro brevioribus bicellulosis, cellulis quadratis, ceramidiis ovato- 

 globosis pedicellatis. (Tab. CXII. C.) 



Hab. Parasitical on Sargassum and Carpophyllum, Colenso. 



A distinctly-marked species, with nearly the same order of branching and habit as P. ceratoclada, but readily 

 distinguished by its four-tubed stem and branches. The articulations are pellucid in all parts of the frond, the cell- 

 walls very thick, and the coloured portion of the cells, viewed laterally in the stem, nearly square. Conceptacles 



occupy the position of a pinnated ramulus on the larger branches. It becomes very dark in drying. Plate 



CXII. ft Pig. 1, plant, natural size ; 2, part of branch, with simple and composite ramuli ; 3, apex of a ramulus • 

 4, cross section of a branch ; 5, a conceptacle (ceramidium) in situ : — more or less magnified. 



vol. ii. 3 N 



