Plate XVII. 



Fig. 71. CLADOSTEPHUS SPONGIOSUS. 



Colour. Dull-brown or dirty olive-green. 

 Suhstance. Rigid; rough; spongy. 



Character of Frond. A clumsy little busli. Branches thick, obtuse, cylin- 

 drical; irregularly forked {dicliotomous). Densely (but irregularly) 

 clothed with short branchlets, so thickly crowded that they overlap 

 each other. Branchlets jointed; falling off in winter. 



Measurement. From o 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 G. verticillatus, by the irregular distribution of the summer 

 branchlets ; contrasting unfavourably with the orderly frills {wliorls) of them at 

 regular distances in G. verticillatus. For G. verticillatus refer back to Plate XIY. 

 Fig. 58. 



Fig. 72. SPHACELAKIA FILICINA. 



Colour. A beautiful green- olive. 



Suhstance. 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. Yery rare. 



'^o description can do justice to this beautifully delicate little plant. Were 

 it the bandywork 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 subject 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. 



33 p 



