Fig. 93. ECTOCARPUS LITTORALIS. 



Colour. Olive-brown^ or olive-green; not unfrequently rust-coloured. 



Substance. Soft^ though coarse^ when young; rigid when old. 



Character of Frond. Dense^, interwoven tufts of jointed threads (filaments). 

 Filaments harsh when old; much and irregularly branched. Main 

 stems often entangled; the lesser divisions free. Branches alternate, 

 on each side a stem; branchlets often opposite. 



Alcasiirement. From 6 to 12 inches long. 



FrLLctification. Formed in the substance of the branchlets; a portion of 

 which becomes converted into fruit-bearing, pod-like formations [sili- 

 cules), causing dark oblong swellings; the tip of the branchlets appearing 

 beyond. (See figure.) 



Habitat. All round our coasts. Parasitical on the larger algge, &c. Between 

 tide-marks. Very common. 



Fig. 94. ECTOCARPUS LONGIFRUCTUS. 



Colour. Olive-green. 

 Suhstance. Soft, though coarse. 



Character of Frond. Large tufts of jointed threads {filaments). Filaments 

 robust; excessively branched. Branches mostly opposite; the lesser 

 ones set with short, thorn -like, opposite (rarely, alternate) branchlets. 



Measurement. Six inches long. 



Fructfication. Formed in the substance of the branchlets; a portion of 

 which becomes converted into fruit-bearing, pod-like formations [sili- 

 cules), causing dark oblong swellings; extending to the tips. (See 

 figure) . 



Habitat. Orkney. Parasitical on algaB between tide-marks. Rare. 



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