126 SEA MOSSES. 



II. Frond flattened or compressed. 



i . Frond forked. 

 (#.) Small, short, wedge-shaped, once or twice 



forked. 

 (i.) Frond thick, smooth, purple or green. 



" Irish Moss," Chondrus. 

 (ii.) Frond channeled, more or less covered 



with papillce, dark. Gigartina. 



(iii.) Frond stalked, thin, narrow, red. 



Gymnogongrus. 

 (b.) Frond long, narrow, partly cylindrical, 

 many times divided. Gracilaria. 



2. Frond pinnately divided. 

 Plant small, pinnae and pinnulse, fine 

 and set in one plane. Ptilota. 



3. Frond irregularly divided. 



Frond forking and branching irregularly, 

 profusely, mostly in one plane, from a 

 marginal point. Euthora. 



Ill Frond filiform or thread-like. 



(From size of sewing cotton to that of 

 wrapping twine, branched). 



1. Plants whose ultimate branehlets taper to both 



ends, 

 (a.) Plants with one main or leading stem. 



