100 ^ THE MARINE BOTANIST. 



completely conceals from view the internal character 

 of the fi'ond, to obtain a knowledge of which it is 

 first necessary to dissolve the Hme by means of an 

 acid, when the structure and affinity of these plants 

 with other members of this series will at once 

 become apparent. 



RHODOMELACE^.— RHODOMELA TRIBE. 



Sea-weeds of a red or brown-red colour, with 

 leafy or thread-like, areolated or articulated fronds, 

 composed of many-sided cells. Fructifications of 

 two kinds : — 1. Ovate or urn-shaped bodies, called 

 ceramidiay containing a tuft of pear-shaped spores. 

 2. Tetraspores in swollen ramuli, or in lanceolate 

 receptacles, termed stichidia. 



All the British genera of this tribe, with the 

 exception of Odonthalia, are slender filiform species, 

 with more or less distinctly articulate fronds ; in 

 the Polysiphonise this structure is clearly visible, 

 while in Dasya the ramuli alone show the joints, 

 and in the three genera, Rhodomela, Bostrychia, 



