Fig. 101. RYTIPHLCEA THUYOIDES. 



Colour. A dull-brown or brownish-yellow; becoming black in drying. 

 Substance. Eobust and elastic. 



Character of Frond. Tliread-like {filamentous); tufted; branched; the 

 filaments opaque^ closely marked with lines across [transversely striate). 

 Stems thread-shaped [filiform); erect; rising from creeping fibres; 

 below^ naked; or set with short spine-like branchlets; abovC;, much 

 branched; branches close, very erect, many times re-branched, but 

 shortly, so as always to preserve a narrow lanceolate outline. 



Measurement. From 3 to 4 inches long. 



Fructification. Of two kinds. 1. Clusters of spores in ovate capsules; external. 

 2. Tetrasjjores in distorted swollen branchlets. 



Habitat. Our coasts generally. In tide-pools, frequent; but not on the X. 

 East coast. 



Fig. 102. RYTIPHLCEA FRUTICULOSA. 



Colour. Dull reddish, or yellowish-brown. 

 Substance. Eobust and elastic. 



Character of Frond. Thread-like [filamentous); tufted; branched; the filaments 

 opaque, closely marked with lines across [transversely striate). Stems 

 forked (spreading widely) from the base; branches the same, partly 

 forked [dichotomous) , partly branched like a feather [pvnnate). Angles 

 of the branches [axils) rounded. Branchlets alternate; horizontal; 

 short; so that each branch has a narrowish outline. 



Measurement. From 3 to 6 inches long. 



Fructification. Of two kinds. 1. Clusters of spores in ovate capsules; 

 external (very rare). 2. Tetraspores in swollen branchlets (common). 



Habitat. Our coasts generally. On sand-covered rocks between tide-marks. 

 Common. 



For the other Bytlp1d<jeas, see Plate XXIV. Fig. 104; and Plate XXV. Fig. 108. 



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