246 SEA MOSSES. 



length of the frond, and the more brilliant pink color, 

 with no admixture of purple, easily distinguish this 

 species from the last. 



C. arach?ioidcu?n, which Harvey figures and 

 describes, Table XXXIII. B., of the "Nereis," Dr. 

 Farlow thinks may be a variety of C. fastigiatiwi, 

 but is in doubt. He declares, on the authority of 

 Agardh, that it is not the same as the species of that 

 name in the European flora. I took it in unlimited 

 quantities, in the little harbor at Wood's Holl, the 

 last of October. It is, indeed, a very beautiful and 

 interesting plant. 



Genus.— PTILOTA* Ag. 



The plants of this genns, which contains two 

 eastern and three western species, are characterized 

 by their cartilaginous, flattened, narrow, pinnately 

 branched, feathery or fern-like fronds. The two 

 eastern species may be easily distinguished by the 

 relative fineness and the place of growth of the two 

 plants; the three western, by certain marked 

 peculiarities of appearance and ramification. 



Ptilota plumosa, Ag. 



The var. serrata of this genus is a very common 



* Ptilota = pinnated, furnished with plumes. 



