Ser. RuoposPpERME. Fam. Rhodomelee. 
Puate VII. 
POLYSIPHONIA FURCELLATA, Zar. 
Gey. Cuar. Frond filamentous, partially or generally articulate ; joints lon- 
gitudinally striate, composed internally of parallel tubes or elongated 
cellules. Fructification twofold, on distinct plants: 1, ovate capsules 
(ceramidia) furnished with a terminal pore, and containing a mass of 
pear-shaped seeds; 2, ¢e¢raspores imbedded in swollen branchlets. 
PorystpHonta—from odds, many, and cipor, a tube; because the 
axis of the frond is composed of several tubes. 
PotysrpHonta furcellata ; filaments elongated, tufted, flexuous, repeatedly 
and closely dichotomous; axils broad, rounded; ramuli erect, their 
points somewhat hooked in ; joints of the stemthree to five times longer 
than broad. 
PoLysrPHoNta furcellata, Harv. in Hook. Br. Fl. vol. ii. p. 332. Man. p. 90. 
Montag. Pl. Cell, Canar. p.172. Endl. 3rd Suppl. p. 45. Kiitz. Ph. Gen. 
p. 425. 
Hurcuinsta fureellata, 4g. Sp. Alg. vol.ii. p. 91. 
Lamovrouxia turgidula, Bonnem. MSS. sec. Ag. 
Has. Very rare. Floating in the sea, at Sidmouth, Mrs. Griffiths and 
Miss Cutler. Dredged in Torbay, Mrs. Griffiths. Carrickfergus, 
Mr. W. Ma Calla (1845). Annual. Summer. 
Geoer. Distr. Atlantic shores of France, Messrs. Bonnemaison and Chauvin, 
sec. Ag. South shore of England. Canary Islands, Wesd. North-east of 
Treland. 
Desc. Filaments as thick as hogs bristle in the lower part, gradually attenuated, 
5—6 inches long, densely tufted and frequently much entangled, excessively 
branched, flexuous or zig-zag, the divisions pretty regularly dichotomous, 
the lower ones subdistant, the upper gradually becoming nearer to each other 
towards the extremities. Axils all remarkably wide; apices either straight 
and subulate, or hooked in; at first simple, finally producing byssoid fibres 
from all the upper articulations. Stem composed of about eight tubiform 
cells surrounding a narrow central tube ; walls of the cells thick, endochrome 
comparatively narrow. Articulations varying in length in different parts of 
the frond ; those of the larger branches 3-5 times, of the lesser about twice, 
and of the ultimate ramuli as long as, or shorter than, their breadth. Colour 
when recent, ‘‘a bright brick-red,’ which changes in the herbarium to a 
deep umber-brown. Substance, according to Mrs. Griffiths, “‘ at first firm, 
but becoming flaccid immediately.” Capsules unknown. ‘Tetraspores fre- 
quently occur in British specimens. 
I have here the satisfaction of figuring for the first time a 
species as rare as it is beautiful, which, till it was recently brought 
by Mr. Webb from the Canary Islands, was supposed to be con- 
fined to the shores of the British Channel. It was first noticed on 
A 
