KEY TO THE GENERA. 133 



(c.) Stem branched and forked ; end of 

 branches beset with many short, stout, 

 oval or obtuse ramuli. ChyloclaJia. 



Frond finer and more elaborately divided. 



(a.) Stem robust, branches irregular; ultimate 

 ramuli, clustered in bunches ; black. 



Rhodoniela. 

 (6.) Frond delicate, many times finely and 

 pinnately divided; color, brown or black. 



Polysiphonia. 

 (e.) Frond delicate, finely pinnated, brilliant 

 pink. Callithamnion. 



