132 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 12 



somewhat irregular; cells sKort, nearly disklike, with central radiating 

 chromatophores, central pyrenoid and excentric nucleus; reproducing 

 without special cell division by the formation of monospores which are 

 liberated by the dissolution of the thallus membranes. 



Goniotrichum Alsidii (Zanardini) Howe 



Taylor 1937, p. 215, pi. 28, figs. 1-4; Smith 1944, p. 161, pi. 35, figs. 

 1 , 2 as G. elegans. 



Mexico: Nayarit, rare as dredged on Bryothamnion from 5-9 meters' 

 depth at sta. 971 near I. Maria Magdalena, Las Tres Marias, no. 39-665 

 (p.p.), 9 May 1939. Colombia: Valle, scarce among filaments of 

 Lejolisia at I. Gorgona, no. 34-495 (p.p.), 12 Feb. 1934. 



BANGIALyngbye, 1819 



Thallus erect, filiform, simple, attached by a small dilated holdfast, 

 terete, subcylindrical or locally constricted; uniseriate or pluriseriate; 

 cells uninucleate with a radiating chromatophore ; reproducing by mono- 

 sporangia resulting from subdivision of the vegetative cells, and also 

 sexually by spermatangia formed by segmentation of the vegetative cells 

 and carpongonia formed by a slight extension from the surface of a vege- 

 tative cell into a receptive trichogyne, the cystocarps resulting being 

 simple, of about eight cells. 



Bangia fuscopurpurea (Dillwyn) Lyngbye 



Taylor 1937, p. 218, pi. 28, f^gs. 10-12. 



One notes that Smith (1944, p. 167, pi. 37, figs. 4-6) recognizes only 

 B. vermicularis Harv. from the West Coast, and that only from central 

 California. The writer was unable to distingush his material from the 

 East Coast and European species, which does reach moderately warm 

 water (Adriatic Sea). However, perhaps his material is only of the un- 

 distinctive early phase of B. vermicularis. 



Costa Rica : locally abundant on very exposed rocks in the surf near 

 low tide line. Port Parker near Ba. Salinas, no. 39-80, 25 Mar. 1939. 



ERYTHROTRICHIAAreschoug, 1850 



Erythrotrichia polymorpha Howe 



Plants filamentous, erect, clustered, to 2.0-2.5 mm tall, 15 jt* diam., 

 of one cell series below with thick outer walls, above very gradually 



