NO. 1 TAYLOR: PACIFIC MARINE ALGAE 245 



Gigartlna leptorhynchus J. Agardh 



Setchell & Gardner 1933, p. 267, pi. 46. 



Mexico: Baja California, common on intertidal more or less sand- 

 covered rocks about South Bay, I. Cerros, no. 34-630 j 10 Mar. 1934. 



Gigartina Ghauvinii (Bory) Montagne 



Setchell & Gardner 1924, p. 744, pi. 70. 



Ecuador: Archipielago de Colon, infrequent and ill-developed in 

 the high littoral, as near Black Beach Anchorage, I. Santa Maria, nos. 

 34-209, 34-222, 17 Jan. 1934. 



Gigartina armata J. Agardh 



Setchell & Gardner 1933, p. 269, pi. 47, fig. 2. 



Mexico: Baja California, on rocks at South Bay, I. Cerros, no. 34- 

 638, 10 Mar. 1934. 



Rhodymeniaceae 



Plants filiform to commonly fleshy membranous and sometimes 

 hollow; w^ith a modified multiaxial type of development, but appearing 

 structurally parenchymatous; asexual reproduction by tetrapartite spo- 

 rangia formed just below the surface; carpogenic branches of three cells, 

 the auxiliary borne upon the same supporting cell beside the carpogonium ; 

 cystocarp with a loose pericarp, discharging by a pore. 



KEY TO GENERA 

 1. Plant with slender firm axis and pyriform to spherical hollow 

 branches Botryocladia 



1. Plant without specialized branchlets 2 



2. Thallus peltate 5 



Thallus not peltate 3 



3. Cystocarps scattered over the face of the fertile segments; the 

 firm membranous thallus dichotomously forking, often margin- 

 ally proliferous 4 



3. Cystocarps marginal ; the soft thallus peltate, round or radiately 

 lobed, or subfoliaceous and irregularly lobed, or dichotomous . 

 Fauchea 



4. Holdfast inconspicuous, percurrent stem absent . . Rhodymenia 



4. Holdfast fibrous, a distinct erect axis bearing lateral forking 

 membranous branches evident Dendrymenia 



5. Thallus soft Fauchea 



5. Thallus firmly fleshy Herpophyllon 



