Fig. 315. CLADOPHORA FRACTA. 
Colour. A dullish green ; more or less light or dark. 
Substance. Eigid ; not adhering to paper. 
Character of Frond. Coarse jointed threads (filaments) growing in long entangled tuftsin 
pools and ditches, where it rises at last to the surface, forming a floating fleece. 
Filaments distantly branched ; the lesser branches somewhat forked, and spreading 
with very wide angles of branching (axils). Branchlets few, alternate, or often 
secund. 
Joints. Very irregular in length. From three to six times as long as broad ; different 
lengths intermixed ; filled with dense, full-green colouring matter, which, under the 
microscope, is evidently formed into little grains (granides). 
Measurement. Indefinite. 
Fructification. As before, except that here and there, when well developed, the zoospores fill 
the joints entirely, so that these become in fact a string of fruit-cells (sporangia). 
This is usually observed about the middle of the frond. 
Habitat. In pools and salt-water ditches as well as in inland lakes. 
Fig. 316. RHIZOCLONIUM RIPARIUM. 
Colour. Light, bright yellow-green (sometimes darker) ; fading very dull in the herbarium. 
Substance. Soft and delicately woolly ; a peculiarity it retains in the herbarium. 
Character of Frond. Long, slender, jointed threads {filaments)\fmg flat on the sides of rocks, 
clothing them with a fine close fleece. Filaments entangled ; here and there 
angularly bent, and sending out from the angles short, horizontal, thorn-like, 
jointed fibres, which rarely lengthen into true branchlets containing colouring 
matter (endochrome). 
Joints. From two to four times longer than broad. 
Measurement. From 1 to 3 inches long. 
Fructification. As before, in the genus Cladophora. 
Habitat. Our coasts generally. (Filey.) On broad faces of sandy’ rocks near high-water 
mark. Not uncommon. 
Fig. 317. CONFERVA ARENICOLA. 
Colour. Pale yellow-green. 
Substance. Soft ; delicate. 
Character of Frond. Extremely fine, jointed threads {filaments) matted together ; creeping ; 
forming a thin fleecy web on the ground. Filaments as slender as human hair 
throughout ; crisped ; wavy ; unbranched. 
Joints. Once and a half as long as broad, when old enough to be observed ; filled with green 
colouring matter {endochrome)., which at last contracts into a dark mass in the centre, 
leaving the rest of the cell pellucid. When young, the threads appear a uniform 
colour throughout, varied only by a few scattered dots. 
Measureme7it. Indefinite. 
Fructification. As before in the genus Cladophora. 
Habitat. On the sandy margins of pools in a salt-marsh periodically flooded.” Eev. M. J. 
Berkeley. 
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