Ser. RHoposrpERMEA. Fam. Rhodomelee 
PuatTe X. 
POLYSIPHONIA RICHARDSONI, Zoot. 
Gey. Cuan. Fyond filamentous, partially or generally articulate; joints 
longitudinally striate, composed internally of parallel tubes or elon- 
gated cellules. Fructification two-fold, on distinct plants ; 1, ovate 
capsules (ceramidia) furnished with a terminal pore, and containing a 
tuft of pear-shaped seeds ; 2, ¢e¢raspores imbedded in swollen branch- 
lets. PotystpHonta—from zodds, many, and cider, a tube; because 
the axis of the frond is composed of many tubes. 
Porystrnon1a Richardsoni; stems cartilaginous, setaceous ; branches alter- 
nate, elongated, divaricate, beset in the upper part with very patent, 
straight, sub-dichotomous ramuli; articulations of the stem and 
branches two or three times longer than broad, irregularly veined ; 
of the ramuli shorter; capsules sessile, globose. 
PotysrpHonta Richardsoni, Hook. Br. Fl. vol.ii. p.33. Harv. Man. p. 90. 
Has. Very rare. At Colvend, Dumfries, Dr. John Richardson. 
GroeRr. Distr. South-west of Scotland. 
Desc. Root scutate. Frond 3-4 inches long, setaceous, rather rigid, with a 
subdistinet, zig-zag stem, very much branched from a short distance above 
the base; the branches issuing at right angles, angularly bent, as long as 
the main stem, subquadrifarious, mostly alternate, beset with distant, very 
patent, subdichotomous, straight branchlets, which bear a few mostly sim- 
ple, erecto-patent or erect, subulate ramuli. 4rticulations visible in the 
main stem, subtorulose, the lower ones three or four times longer than 
broad, spirally or irregularly tubed; the upper shorter, with parallel tubes. 
Capsules globose, sessile, wide-mouthed, situate near the summits of the 
lesser branches. Tubes about five in the stem, each with a deep-coloured 
bag of endochrome. 
What little is known of this species, if it be entitled to that 
rank, is taken from a specimen gathered by Dr. Richardson many 
years ago, before the Arctic Expedition which he accompanied, 
and preserved im Sir W. J. Hooker’s rich Herbartum. Our upper- 
most figure is nearly a fac-simile of that specimen. 
Though it closely borders im its microscopic characters on 
several species, its habit does not precisely agree with any 
with which I am acquainted. The nearest in affinity is perhaps 
P. fibrillosa, and it is possible that it may be only an anomalous 
