THE MARINE BOTANIST. 125 



Laurencia, Frond cylindrical or compressed, pin- 



natified ; the ramuli blunt. 

 Chrysymenia, Frond filled with watery gelatine, 



not constricted or chambered. 

 Chylocladia. Frond contracted at intervals, filled 



with watery gelatine. 



LAURENCIACE^-LAURENCIA TRIBE. 



Sea-weeds of a rose-red or purple-colour, usu- 

 ally with cylindrical, rarely compressed, and still 

 more rarely flattened fronds, destitute of midrib; 

 linear inarticulate, though occasionally as in Chylo- 

 cladia, constricted at regular distances in a joint- 

 like manner. Fructification of two kinds. 1. cera- 

 midia external, ovate in form, containing a tuft 

 of pear-shaped spores. 2. tetraspores immersed in 

 the branches and ramuli, scattered without order 

 through the surface cells. 



The succulent, inarticulate fi:*onds of these plants, 

 having their tetraspores dispersed without order 

 through the ramuli, form the principal difference 

 between them and those of the foregoing tribe. 



