Plate LXVI. 



Fig. 306. CLADOPHORA REPENS. 



Coloiir. Dark green. 

 Substance. Rigid; spongy. 



Character of Frond. Short, dense, cushion-shaped, or globular tufts of jointed 

 threads (^filaments). Filaments slender; closely matted together; rising from 

 root-like fibres; slightly branched. Branches simple or forked; upright or 

 oddly bent; bare, or clothed with a few distant, secund branchlets. 



Joints. From ten to twenty times their width; cylindrical throughout; i. e. not 

 swollen upwards like those of C. Brow nil; filled with green colouring matter 

 (endocJirome). 



Measurement. Tufts an inch or 2 in diameter. Filaments scarcely J an inch high. 

 Fructification. Minute seeds (zoospores) formed of the colouring matter in the joints, 



and in due time bursting through them. 

 Halitat. Jersey. Once picked up there after a gale. 



Fig. 307. CLADOPHORA NUDA. 



Colour. Dark green; or olive when dry. 

 Substance. Somewhat rigid. 



Character of Frond. Loose tufts of jointed threads [filaments), sparingly branched. 



Filaments slender; very straight; here and there forked {dichotomous). 



Branches set with a few scattered, very upright, rod-like, close-lying branchlets; 



the angles of branching (axils) being very narrow. Uppermost branchlets 



often opposite and long, so that the tips of the branches appear three-forked 



(not expressed in the plate.) 

 Joints. Six or eight times longer than broad; filled with green colouring matter 



(endochrome). 

 Measurement. Two or 3 inches high. 



Fructification. Minute seeds (zoospores) formed of the colouring matter in the joints, 



and in due time bursting through them. 

 Habitat. Portstewart. On basalt rocks in the sea. Unknown elsewhere, and only ^ 



once seen there. 



Fig. 308. CLADOPHORA LANOSA. 



Colour. Yellow-green; fading pale, and quite without gloss when dry. 

 Substance. Soft; spongy. 



Character of Frond. Short, dense, globular tufts of jointed threads (filaments); 

 sparingly branched, forming a circle when laid out. Filaments hair-like; 

 woolly; matted together; throwing out fibres from the lower joints. Branches 

 straight, rod-like, alternate or rarely opposite; set with a few alternate or 

 secund branchlets. Angles of branching (axils) very narrow. 



Joints. The lower ones twice, the upper six times as long as broad; filled with pale 

 green colouring matter (endochrome). 



Measurement. An inch high. 



Fructification. Minute seeds (zoospores) formed of the colouring matter in the joints, 



and in due time bursting through them. 

 Habitat. Our coasts generally, but prefers the north. Parasitic on various algse; 



often on Folyides rotundus; occasionally on rocks. Common. 



57 * I 



