58 COMMON SEAWEEDS. 



PTILOTA SEEICEA. 



(SILKY PTILOTA.) 

 (Ptilota from a Greek word signifying c * pinnated.") 



In company with Chylocladia under the hanging 

 rock is this beautiful feathery seaweed : its sister- 

 plant Ptilota Plumosa, more rare and lovely, is found 

 at lowest-water mark, or cast up after a storm. 



The texture of this seaweed is worthy of micro- 

 scopic examination. The frond is not jointed, but the 

 branches which divide and subdivide are composed of 

 minute cells filled with pink fluid, and with transpa- 

 rent divisions : the fruit is often abundant. Favellce, 

 or large cells having a dense mass of spores within 

 them, are found at the tips of the branches, generally 

 only two of them, partially sheltered by short branches. 

 Tetraspores are found in rows upon the ramuli, little 

 dots of white cells enclosing red spores. 



GKIEEXTHSIA. 



(Named in honour of Mrs. Griffiths, of Torquay, Devon, whose many 

 discoveries in and intimate knowledge of seaweeds are well known in 

 the scientific world.) 



A most valuable family of seaweeds for the col- 

 lector's album. There are seven species. 



Generic character. — Frond rose-red, thread-like, 

 jointed slightly, branched, sometimes whorled, and 

 the joints transparent. 



Fructification. — 1. Roundish gelatinous receptacles 

 or favellce containing minute spores. 2. Tetraspores, 

 affixed to whorled ramuli or lesser branches. 



