Fig. 222. PTILOTA SERICEA. 
Colour. Usually a dull, brownish-red ; sometimes brighter. Brown when old. 
Substance. Very soft and limp ; sometimes dense and almost spongy. 
Character of Frond. Thread-like {filamentous) but compressed; excessively branched in a 
formal manner. Main stems irregularly divided ; rough below with minute branch- 
let stumps. Branches re-branched ; with short, curved, exactly opposite, horizontally- 
spread branchlets. These re-branchleted once or twice in the same way. Stem and 
branches opaque. Branches jointed. (See figure of a magnified bit.) 
Measurement. From 2 to 6 inches long. 
Fructification. Of two kinds. 1. Clustered globules of spores., surrounded with six or eight 
minute, slender branchletems {ramelli), which fold over them {involucrated) ; stalked ; 
formed at the end of the shortened branchlets. 2. Globules of tetraspores formed 
in the tips of the same. 
Habitat. Our coasts generally. On perpendicular rocks between tide-marks. Barely on the 
stems of Fucus serratus. Common. 
Now Ptilota eleyans. This is the only Ptilota found on the south coast of England. 
Fig. 223. PTILOTA PLUMOSA. 
Colour. A fine dark red ; sometimes very clear and bright. 
Substance. Gristly and firm. 
Character of Frond. Thread-like {filamentous), but flat ; excessively branched in a formal 
manner. Main stems irregularly divided ; smooth ; set with branches of irregular 
lengths. Branches re-branched ; secondary set (and sometimes the primary) clothed 
throughout with shortish, curved, wide-spread branchlets. These re-branchleted once 
or twice in the same way. Stem branches and branchlets unjointed ; opaque. 
Measurement. From 3 to 14 inches long. 
Fructification. Of two kinds. 1. Clustered globules of spores, surrounded with six or eight 
minute, slender branchletee^zs {ramelli), which fold over them ; stalked ; formed on the 
end of the then shortened branchlets. 2. Globules of tetraspores formed in the tips 
of the same. 
Habitat. Northern and western coasts of Great Britain and Ireland. On the stems of Lam. 
digitata. Frequent. 
The first set of branchlets are often not re-branchleted quite close to their base, so that the 
bare spaces look like a narrow white line between them and the stem. This is not the case 
in P. sericea, so that it serves as a clue between the species. 
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