8 Cliarles E. Bessey 



this phylum, nearly all of which are marine, contain phycoerythrin 

 in their cells, which gives them a red or purple color. 



Class 13. BANGIOIDEAE. Antherids and oogones devel- 

 oped from ordinary cells of the plant body by a slight enlarge- 

 ment, the former producing non-ciliated sperms, and the latter 

 scarcely differentiated single eggs ; no trichogyne. Species about 

 50, doubtfully referred to this phylum. 



Order Bangiales. Plants filamentous or stratose ; propagation 

 by monospores (undivided tetraspores) ; chromatophore one in 

 each cell, stellate. 



Family i. Bangiaceae. Composed of a few genera, and from 

 forty to fifty species, including the edible " laver' ' (species of 

 Porphyra). (Pf. I, 2, 307.) 



Order Rhodochaetales. Plants filamentous, erect, branched ; 

 propagation by monospores ; chromotophores several to many in 

 each cell. 



Family 2. Rhodochaetaceae. Filaments not corticated. But 

 one genus, Rhodochaete, containing a single marine species. (Pf. 

 I, 2, 316.) 



Family 3. Campsopogonaceae. Filaments corticated. But one 

 genus, Campsopogon, containing a few freshwater species. (Pf. 

 I, 2, 318.) 



Class 14. FLORIDEAE. Red Seaweeds. Antherids com- 

 posed of definite groups of cells, superficial or on branches, pro- 

 ducing non-ciliated sperms ; oogone a single cell prolonged above 

 into a long fine hair, the trichogyne, and containing a definite tgg 

 in its base. (Species about 3,000.) 



Order Nemalionales. Lower Red Seaweeds. Mostly fila- 

 mentous plants : the fertilized oogone gives rise directly to the 

 erect or more or less spreading, tufted sporophores ("gonimo- 

 blasts"), which are naked, or enclosed in a protective envelope. 



Family 4. Lemaneaceae. Plants consisting of delicate branch- 

 ing threads, living in fresh water. Lemanea. (Pf. I, 2, 324.) 



44 



