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LIST OF THE BBITISH 



LVII. Gracilaria. 



Frond filiform (rarely flat), cellular. Fructification : — 



1. Convex tubercles, containing a mass of minute spores ; 



2. Tetraspores imbedded in the cells of the surface. 



1. Gracilaria multipartita. 



2. „ compressa. 



3. 3 , confervoides. 



4. „ erecta. 



LVIIL Hypnea. 



Frond filiform, cartilaginous, much branched, cellular. 

 Fructification: — 1. Spherical tubercles, immersed in the 

 ramuli ; 2. Tetraspores imbedded in the surface-cells. 



1. Hypnea purpurascens, 



Order XII. CRYPTONEMIACEiE. 



Purplish or rose-red sea-weeds, with a filiform or 

 (rarely) expanded, gelatinous or cartilaginous frond. 

 Fructification : — 1. Globose masses of spores immersed 

 in the frond, or in swellings of the branches ; 2. Tetra- 

 spores variously dispersed. 



