Fig. 126. POLYSIPHONTA FURCELLATA. 
Colour. When recent, a bright brick-red ; turning umber-brown when dry. 
Substance. At first firm, but becoming soft immediately. 
Character of Frond. Very slender tufts of jointed threads {filaments) much entangled, wavy, 
excessively branched. All the branching regularly and repeatedly, and, in the upper 
part, very closely forked {dichotomous) ; angles of branching {axils) broad and 
rounded ; branchlets upright, their points somewhat hooked in. Joints visible through- 
out ; marked with several slender, upright lines (internal tubes) vdiich sometimes 
cross each other. 
Internal Tubes. About eight. 
Measurement. Five or 6 inches long. 
Fructification. Not found in Britain. 
Hahitat. South shore of England and Ireland. Jersey. Found floating or by dredging. Very 
rare. 
Fig. 127. POLYSIPHONIA FASTIGIATA. 
Colour. Dark-brown ; reddish in deep water ; becoming yellowish on exposed rocks left by the 
tide ; drying quite black. 
Substance. Eigid. 
Character of Frond. Dense, globular tufts of jointed threads {filaments) excessively branched 
from the base. Filaments as thick as hogs’ bristles, and of equal diameter throughout 
the plant. All the main branches forked {dichotomous) ; their angles of branching 
{axils) wide. Branchlets rather less regular ; being occasionally alternate. All the 
tips of the same length as if they had been cut to one level (forming a circle when 
laid out). Joints visible throughout ; marked with numerous upright lines (internal 
tubes) ; a dark central spot in each. 
Internal Tubes. Sixteen or eighteen. 
Measurement. From 2 to 4 inches long. 
Fructification. Of two kinds. 1. Clustered spores in ovate-stalked capsules., with a narrow, pro- 
truding mouth ; external. 2. Tetraspores., immersed in swollen, distorted branchlets. 
Habitat. Our coasts generally. Parasitic on Fucus nodosus, and Fucus vesicidosus ; but 
especially the former. Very common. 
Fig. 128. POLYSIPHONIA PARASITICA. 
Colour. A clear lake-red ; becoming brownish in drying. 
Substance. Eigid, but not harsh. 
Character of Frond. Delicate, feather-like tufts of jointed threads {filaments)., very much 
branched. Stems rather compressed ; simple. Branches alternate, generally short 
below, longer above ; once or twice re-branched like a feather {pinnated) ; last 
branchlets simple, awl-shaped, acute, upright, alternate, closely set. Joints visible 
throughout ; marked with 'three or four lines (internal tubes) with transparent spaces 
between. 
Internal Tubes. About eight. 
Measurement. From | inch to 1^ long. 
Fructification. Of two kinds. 1. Clustered spores in large ovate, shortly-stalked capsules ; 
external (very rare). 2. Tetraspores, immersed in swollen, much distorted branchlets. 
Habitat. Our coasts generally. Sometimes parasitic on the larger algae. Oftener in pools 
near low-water mark ; growing on the pink incrustations formed by Corallinas and 
Melobesias; where few other plants are to be seen. 
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