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LIST OF THE BRITISH 



3. Nitophyllum Bonnemaisonii. 



4. „ G-melini. 

 6. laceratum. 

 6. ,, versicolor. 



LIII. Plocamium. 



Frond pinky-red, linear, compressed or flat, ribless, 

 distichously much branched. The ramuli alternate, 

 acute. Fructification of two kinds. 



1. Plocamium coccineum. 



Order XI. RHODYMENIACEiE. 



Purplish or blood-red sea- weeds, with an expanded or 

 filiform, inarticulate frond. Fructification double : — 1. 

 Conceptacles external, or half immersed, containing, 

 beneath a thick pericarp, a mass of spores ; 2. Tetra- 

 spores either dispersed through the whole frond, or col- 

 lected in indefinite, cloudy patches. 



