Plate LI. 
Fig. 230. MICROCLADIA GLANDULOSA. 
Colour. A fine rose-red. 
Substance. Membranaceous, tbougli firm. 
Character of Frond. Thread-like {filamentous)., though compressed ; of nearly the same width 
throughout ; tufted ; much branched from the base, in an alternate or irregularly forked 
manner ; forming a roundish outline. Angles of branching {axils) wide-spread ; last 
branchlets short ; tips either awl-shaped or split, in which case they resemble pincers. 
Measurement. One or 2 inches long. 
Fructification. Of two kinds. 1. Masses of spores in roundish capsules ; surrounded by two 
or three short branchletee/is {ramelli ) ; sessile on the margin of the branches. 
2. Tetraspores imbedded in the tips of the same. 
Habitat. South and east coasts of England and Ireland. Hompton (N. of Hull). Bray. 
Kingstown. Scilly. 
Fig. 231. CERAMIUM DECURRENS. 
Colour. A dull purplish-pink. 
Substance. Soft. 
Character of Frond. Tufts of jointed threads (filaments) ; much branched. Filaments thicker 
than hog’s bristles below, gradually finer upwards ; distinctly forked ; naked, or 
furnished with a few scattered branchlets ; the tips hooked inwards. 
Joints. Partially coloured ; a narrow transparent space in the centre of each (see figure), the 
coloured portion melting gradually into the white. 
Measurement. Prom 6 to 8 inches long. 
Fructification. Not observed. 
Habitat. Our coasts generally. On rocks and the smaller algse in tide-pools. Bare. 
Fig. 232. CERAMIUM GRACILLIMUM. 
Colour. A dark reddish-purple. 
Substance. Very soft, tender, gelatinous. 
Character of Frond. Tufts of jointed threads {filaments) ; much branched. Filaments exces- 
sively slender, more so than a human hair ; of nearly the same thickness throughout ; 
regularly forked, or nearly so ; the branches set with minute many-times-divided 
branchlets, spreading fan-wise ; the tips slightly hooked. 
Joints. Colourless. Partition-lines {dissepiments)^ opaque, purple. 
Measurement. From 2 to 3 inches long. 
Fructification. Only one kind observed. Minute spores in large, roundish capsules, sessile on 
the branchlets, often two together. With several slender branchletee? 2 s, ray-like, 
spreading below them ; their tips forked. 
Habitat. South of England and west of Ireland. On Corallina ojficinalis, &c. between tide- 
marks. Not common. 
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