NO. 1 TAYLOR: PACIFIC MARINE ALGAE 131 



Rhodophyceae 



Plants generally rose or purplish red, filamentous or parenchymatous, 

 of very varied forms; accessory pigments, particularly phycoerythrin, 

 generally masking the chlorophyll, in definite chromatophores ; reproduc- 

 tion generally involving one sexual phase and one or two different asexual 

 phases, the cycle when of two stages showing a relatively well-developed 

 sexual phase or gametophyte and a compact attached dependent carpo- 

 sporophyte produced after fertilization from the zygote, but when of 

 three phases an additional tetrasporophyte phase is intercalated between 

 the carposporophyte and the next gametophyte, and is morphologically 

 similar to the latter; sexual organs composed of nonflagellate spermatia 

 produced singly in spermatangia, and carpogonia which in the simple 

 genera are produced from the surface thallus cells, but which in the higher 

 genera are the terminal cells of specialized filaments or carpogenic 

 branches, and consist of an enlarged base and a receptive projection or 

 trichogyne; carposporophyte produced directly or indirectly from the 

 carpogonium, more or less completely converted into carpospores at ma- 

 turity; tetrasporophyte producing sporangia laterally on the filaments, in 

 the cortex or in specialized branches, these generally each forming four 

 nonmotile spores. 



Bangiaceae 



Plants filamentous or membranous, when filamentous the filaments 

 simple or branched, or creeping and even associated to form disks; cells 

 usually with axial, sometimes with parietal chromatophores; asexual re- 

 production by monospores ; sexual reproduction when present by spermatia 

 and carpogonia, the zygote developing several carpospores. 



KEY TO GENERA 



1. Plants filiform throughout 2 



1. Plants membranous 3 



2. Unbranched, becoming pluriseriate Bangia 



2. Branched, uniseriate Goniotrichum 



3. Plants forming minute, strap-shaped blades only a few cells wide 

 Erythrotrichia 



3. Plants very much larger, foliaceous Porphyra 



GONIOTRICHUM Kiitzing, 1843 



Thallus erect, filamentous, dull rose red, pseudodichotomous or rarely 

 laterally branched, below attached by thickened cells, above terete or 



