BHODOMELi.CB.fi. 71 



tubes. Tt moreover resists the action of fresh water for a 

 Longer time, and (lie colour is also different. Some speci- 

 mens of P. elongella have a Blight Loos of our plant, but 

 usually their peculiar ramification sufficiently marks these 

 Bpec 



113. elong-ella (The divaricate Polysiphonia) \ filaments 

 oeoufl and rigid below, gradually attenuated upward-, irregu- 

 larly dichotomouB, with very patent axils; upper branches 

 flaccid, more or Less furnished with lateral, pencilled, mul- 

 tifid, rose or blood-red ramuli ; articulations of the branches 

 about as long as broad, those of the ramuli rather Longer, 

 both marked with 2-3 broad, parallel, oblong cells; primary 

 tubes lom-, surrounding a minute cavity, and encomp 

 with an •external coat of small cells; capsules ovate, on a 

 short stalk ; dissepiments pellucid, Ham. in Hook. Br, PI. 



■ 2. p. 334 (Atlas, PL XXVI. Fig. 117.) 



Sab. On rocks and -tones, and on the smaller AlgSB, near low- 

 water mark, and at a greater depth. Biennial. Spring and 

 summer. Bather rare-. 

 The winter and summer aspects of a deciduous tree are 

 not more different from each other than are specimens of 

 this beautiful plant collected at opposite Beasons. Our 

 figure represents it when in perfection, as it is in Bpring 

 ami in the early months of summer, when its branches are 

 clothed with abundant pencils of delicate rosy or blood-red 

 ramuli. At a later period of the year these tall away, and 

 the specimens collected in September or October are usu- 

 ally quite bare, the larger branches only remaining ; and 

 these in their nakedness and rigidity, with broken points 

 and spine-like divaricating branches, have little resemblance 

 to the plant of summer. Such specimens as survive the 

 winter throw out with returning Bpring fresh pencils of 



branchlets, even in greater profusion than the first year. 

 Such is also the ease with /'. eloitgata, which OUT J\ elofl- 



gella strongly resembles in miniature, but from which it 

 may readily be known by the pellucid articulations visible 

 in all parts of the plant, and by the ramuli not tapering to 

 the base. 



114. elongata (77/e Lobster-horn Poli/siphonia) \ Btems robust, 

 cartilaginous (rarely gelatinous), irregularly branched, 

 especially towards the tips, with Blender, close-set, multifid 



ramuli, which are attenuate to the ha-e and ape\ : articula- 

 tions about as lon_ r as broad (the upper pnes rareh once and 

 a halt to twice as Long), those of the stem reticulated 



