Fig. 309. CLADOPHORA UNCIALIS. 



Colour. Yellowish-green; but more grassy than the preceding, and not fading so 



pale when dry; the tips occasionally bright. 

 Substance. Soft and spongy. 



Character of Frond. Short, dense tufts of jointed threads {filaments), sparingly 

 branched. Filaments hair-like; woolly; wavy; the older ones inextricably 

 matted together, but in several thick subdivisions throwing out fibres. 

 Branches irregular; set with a few distant, secund, long, spreading or incurved 

 branchlets. 



Joints. From two to four times longer than broad; filled with green colouring 



matter {endoclirome). 

 Measurement. An inch high. 



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



and in due time bursting through them. 

 liahitat. Our shores generall}''. On rocks near low-water mark. Common. 



Fig. 310. CLADOPHORA ARCTA. 



Colour. A brilliant, g-lossy, grass-green when young; olive and dull when old; at 

 "a certain age" olive and dull below; glistening at the tips, which being in 

 fact the youngest shoots of the plant, change last. 



Substance. Soft, and retaining water at all times; coarse and very spongy when old. 



Character of Frond. Broad, star-like tufts of jointed threads {filaments) rising from 

 a wide disc of matted fibres. Filaments as thick as horse-hair; spreading in 

 a circle; much branched. When young, clothed with straight, crowded, very 

 upright, alternate or opposite branches; bearing branchlets of the same 

 character, but often secund branchlets. When old, matted into rope-like 

 bundles below, by root-like fibres from the joints; the upper branchlets only 

 free. 



Joints. Extremely variable in length; the lower, however, generally only once or 

 twice as long as broad, the upper many times longer; filled with green 

 colouring matter {endoclirome). 



Measurement. From 2 to 4 inches high. 



Fructification. As befoi-e. 



Habitat. Our coasts generally. On rocks from half-tide level to low-water mark. 

 Common. 



Fig. 311. CLADOPHORA GLAUCESCENS. 



Colour. A bright but scarcely grass-green; varying, however, in different specimens. 

 Substance. Soft and rather silky; having a speckled, shimmering look when dry, and 



seen through a pocket lens. 

 Character of Frond. Dense tufts of jointed threads {filaments), excessively branched. 



Filaments very wavy; hair-like (but not so slender as those of C. refracta), 



furnished with straight, erect, alternate branches, several times re-branched; 



the lesser ones closely set with very upright, long, finely drawn out, alternate 



or secund branchlets. 



Joints. About three times as long as broad; nearly uniform throughout; filled with 



green colouring matter {endochrome). 

 Measurement. Two or 3 inches long, generally; but occasionally up to 6. 

 Fructification. As before. 



Habitat. Our coasts generally. On rocks and stones between tide-marks. Common. 



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