Fig. 354. SCHIZOSIPHON WARRENIJE. 



Colour. Dark green. 

 Substance. Soft; fleshy; slimy. 



Character of Frond. Roundish, irregularly-spreading lumps, running together, and 

 forming a glazy crust upon rocks; formed of closely-packed threads {filaments) 

 radiating from a centre. 



Internal Filaments. Tubular; containing cylindrical colour-cells, which show through; 

 set in wide transparent sheaths, composed of innumerable upright, hair-like 

 gelatinous shreds; so closely set as to look entire, all but the tips. A nearly 

 globose cell at the bottom of each (a microscopic object). 



Measurement. The patches spreading indefinitely. 



Fructification. Minute seeds {zoospores) formed of the coloured cells in the filaments; 

 which cells then separate from each other and drop out. 



Ilahitat. Coast of Devonshire. On rocks at high- water mark; chiefly in places ex- 

 posed to the drip of fresh water. 



Fig. 355. SCHIZOTHEIX CEESWELLII. 



Colour. The tuft greenish-olive; the threads which con^pose it, yellowish-green. 



Sulstance. The tufts soft; sj)ongy; the threads which compose it rigid. 



Character of Frond. Dense, cushion-like tufts, spreading on the surface of rocks in 

 round or oval patches; composed of very slender threads (^filaments) collected 

 into branching bundles. Filaments curved, interlaced, branched in a forked 

 manner (a microscopic object). 



Measurement. The patches several inches across. 



Fructification. Not ascertained. 



Hahitat. On sandstone rocks near high- water mark; exposed to the drip of fresh water. 



Fig. 356. CALOTHEIX CONFERVICOLA. 



Colour. A fine, deep, metallic green; reflecting prismatic colours under water. 

 Sulstance. Rigid for so tiny a plant. 



Character of Frond. Minute, starry tufts of threads {filaments) only a few in each; 



scattered over the fronds of other algse, and often covering them altogether. 



Filaments tubular; containing very narrow, cylindrical colour-cells, which show 



through, with division-lines. 

 Measurement. Never more than J inch high; often less. 

 Fructification. As in Schizosiphon and Rivularia. 



Hahitat. Our coasts generally. On small algse between tide-marks. Abundant in 

 the autumn. 



This charming little parasite, instead of disfiguring the plant on which it 

 grows, often makes it a good deal handsomer than it was before. For instance, 

 it is specially fond of the pale, sickly-looking Ceramium ruhrum, which grows 

 in high-water pools, and this it adorns with a fringe of dark green. Some 

 unusual appearances are figured in the outer magnified form on the Plate. 

 They are not understood. 



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