Plate XVII. 
Fig. 71. CLADOSTEPHUS SPONGIOSES. 
Colour. Dull-brown or dirty olive-green. 
Suh stance. Eigid ; rough ; spongy. 
Character of Frond. A clumsy little bush. Branches thick, obtuse, cylindrical ; irregularly 
forked (dichotomous'). Densely (but irregularly) clothed with short branchlets, so 
thickly crowded that they overlap each other. Branchlets jointed ; falling off 
in winter. 
Measurement. From 3 to 4 inches long. 
Fructification. Oval seeds (^spores) ; stalked ; borne on a special set of minute branchlets which 
grow irregularly over the branches when the summer set dies off. 
Habitat. Our coasts generally. On rocks and stones between tide-marks. Common. 
Known from O. verticillatus, by the irregular distribution of the summer branchlets ; 
contrasting unfavourably with the orderly frills (tvhorls) of them at regular distances in 
C. verticillatus. For C. verticillatus refer back to Plate XIV. Fig. 58. 
Fig. 72.- SPHACELARIA FILICINA. 
Colour. A beautiful green-olive. 
Substance. Firm, somewhat rigid, but delicate. 
Character of Frond. Delicately bushy. Stem and branches jointed throughout; thread-like 
{filiform). Stem shaggy at base ; slender ; irregularly branched ; often bearing at 
the top several branches displayed like a fan. Branches alternate. Branches and 
branchlets twice branched ; lanceolate in outline ; all the angles of branching acute. 
Measurement. From 2 to 4 inches long. 
Fructification. Oval seeds {spores) borne on the branchlets in winter. 
Habitat, South of England and Ireland ; Jersey. Very rare. 
No description can do justice to this beautifully delicate little plant. Were it the 
handywork of man, we should exclaim at the exquisite skill betrayed by its elaborately 
worked-out and tasteful construction. This species, like all its relatives (congeners), is sub- 
ject to what is considered a withering of the tips of the branchlets, which become partially 
colourless, partially filled with a dark substance, the nature of which is not known. 
P 
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