Plate LXIII. 

 Fig. 294. CLADOPHOKA PELLUCIDA. 



Colour. A fine, glossy, transparent green; fading in the herbarium. 

 Substance. Rigid; wiry; adhering very imperfectly to paper. 



Character of Frond. Thread-like {filamentous); jointed; solitary or slightly tufted; 

 distantly, much branched. Stems as thick as a hog's bristle; undivided at 

 first; then forked {dichotomous), or three- (or even four-) armed (tricJiotomous) ; 

 and, more or less, regularly continuing this character throughout. Upper 

 branches furnished with branchlets of the same three-armed growth; or 

 occasionally tufted. Branches re-branchleted. 



Joints. From three-quarters of an inch to an inch long below; shorter upwards; 

 branches springing from all the partition-lines {dissepiments) ; filled with green 

 colouring matter {endoehrome). 



Measurement. From 4 to 6 inches long. 



Fructification. Minute seeds {zoospores^', so called from having at one period a 

 motion as if endowed with animal life); formed of the colouring matter in 

 the joints; and in due time bursting through them. 



Salitat. Our coasts generally. In deep rock-pools near low-water mark. Not very 

 common. 



* This explanation of the word zoospores need not, surely, be continued longer. 

 C. pellucida is, from its extremely long joints and three-armed branching, a 

 quite clearly marked British species. 



Fig. 295. CLADOPHOKA RECTANGULARIS. 



Colour. A full green; fading in the herbarium. 



Suhstance. Rigid; bristling; adhering very imperfectly to paper. 



Character of Frond. Thread-like (filamentous); jointed; several growing near 

 together and entangled in intricate bundles; distantly, much branched. 

 Filaments as thick as hogs' bristles throughout; set with long, wavy, wide- 

 spread, exactly opposite branches; or, occasionally, irregularly divided. 

 Branches rebranched in the same way; more or less furnished with very short, 

 exactly opposite, horizontal branches, which are sometimes simple; sometimes 

 re-branchleted with a second similar set. 



Joints. Twice or thrice as long as broad throughout; filled with green colouring 

 matter {endochrome) . 



Measurement. From 8 to 12 inches long. 



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

 and in due time bursting through them. 



'Habitat. Abundant in Roundstone Bay. Arran. Torquay. Thrown ashore. Very 

 rare generally. 



Another most clearly marked species; but, unluckily, extremely rare. The 

 tiny, exactly opposite branchlets, are found on no other British Cladophora. 

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