Ser. RHODOSPERMEX. Fam. Rhodomelee. 
Pirate CCXXVIII. 
POLYSIPHONIA GRIFFITHSIANA, Za. 
Gey. Cuan. Frond filamentous, partially or generally articulate; joints 
longitudinally striate, composed of numerous radiating cells or tubes, 
disposed round a central cavity. Fruetification two-fold, on different 
individuals; 1, ovate capsules (ceramidia), furnished with a terminal 
pore, containing a mass of pear-shaped spores; 2, ¢etraspores im- 
bedded in swollen branchlets. PotystpHonta (Gev.),—from 7odvs, 
many, and oper, a tube. 
PotystPHonta Grifithsiana; stem rigid, attenuated, alternately branched ; 
branches long, patent, subsimple, furnished with numerous subdicho- 
tomous or alternately divided, slender, patent, flaccid ramuli; articu- 
lations of the stem, branches, and ramuli about once and a half or rarely 
twice as long as broad, with straight tubes; siphons in the stem four, 
with four alternate secondary ones; capsules broadly ovate, sessile. 
PoLysrPHoNtA Griffithsiana, Harv. Man. p: 91. 
Has. On the smaller Alge between tide-marks. Annual. September. 
Parasitical on Polyides rotundus at Torquay, Mrs. Griffiths. Isle of 
Portland, Miss White. 
Geoer. Distr. South coast of England. 
Descr. Root a small disc. Fronds laxly tufted, four to five inches long, and 
nearly as much in expansion. Stem undivided, set throughout its length 
with alternate, spreading branches, the lowest of which are longest, the rest 
gradually shorter upwards, giving the whole frond a pyramidal outline. 
Branches like the stem, beset with a second and third series of alternate lesser 
branches, the last of which are more or less furnished with dichotomous, flaccid, 
slender ramuli. All parts of the frond are conspicuously jointed ; the articula- 
tions of the stem are from one and a half to twice as long as broad, marked 
with about five tubes, two of which are much narrower than the rest ; those of 
the branches are about once and a half as long as broad, with two tubes 
only. A transverse section of the stem shows four primary and four 
secondary tubes. Ceramidia ovate, sessile, scattered on the ramuli. Colour 
a full red, inclining to brownish in drying but not much altered by fresh 
water. Swéstance rather rigid in the stem and branches, flaccid in the 
ramuli. 
An elegant plant with a good deal the habit of small specimens 
of P. violacea, but known at once from that species by the dis- 
tinctly jointed stem marked by straight tubes. It moreover resists 
the action of fresh water for a longer time, and the colour is also 
different. Some specimens of P. e/ongella have a slight look of 
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