246 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 17 



small cells ; medulla of sparse, ramified, slender filaments ; tetrasporangia 

 scattered through the cortex just below the surface, 18-25 fi long, ovate, 

 appearing rather conspicuously large in the cortex, which is not ne- 

 mathecially modified; gonimoblast development apparently as in G. 

 filicina; cystocarps scattered through the thallus, embedded on either 

 side beneath a small ostiole, their development causing a slight to moder- 

 ate elevation of the thallus surface; antheridia entirely superficial, pro- 

 duced over whole thallus surface beneath a thin, colorless surface matrix. 



The above description is drawn up from type material. 



Type: Holotype not designated. Syntypes collected by N. L. 

 Gardner, June 10, 1906, were distributed as no. CXXIV, A-B, in 

 Phycotheca Boreali-Americana. The material in HAHF includes cT ? 

 and specimens. 



Type locality: On rocks at low tide level. Fort Point, San 

 Francisco, California. (Some of Gardner's Fort Point material is 

 labeled "% mile inside the bay from the Fort.") 



Mexican distribution: Pacific Baja Calif. — D. 161, in drift 1 

 mile south of Cabo Colnett, Jan. ; D. 8673, fragments in drift along bay 

 shore southeast of Punta Baja, Jan. 



This species appears usually to be of sublittoral occurrence along the 

 Pacific Coast from Oregon to Baja California. Its very small holdfast 

 would seem to make it ill-suited to intertidal localities except in such 

 favorably protected ones as near Fort Point within San Francisco Bay. 

 In southern California specimens have been dredged from a depth of 26 

 meters oflF San Pedro (D. 8116). It is interesting to note that both 

 Mexican collections are from areas of minimum inshore temperature for 

 that coast (Dawson 1951). 



Grateloupia howei Setchell & Gardner 

 PI. 1, fig. 2; PI. 6, fig. 47 



Setchell and Gardner 1924, p. 782, pi. 83; Dawson 1944, p. 281; 

 Dawson 1950, p. 153, fig. 28. Gigartina eatoniana J. Ag., as interpreted 

 by Dawson 1944, p. 301. 



Mature thalli 10-30 cm. high, consisting of one to several complan- 

 ate, variously pinnately branched, divided and (or) lobed blades from a 

 small discoid holdfast; branches initiated early in juvenile plants, with 

 narrow segments (1-2 mm.), the lower ones remaining narrow and com- 

 pressed in age; blades expanding gradually from narrow basal parts to 

 (10)-15-30 mm. in width (rarely to 50 mm.), sometimes remaining sub- 

 simple or only dichotomously divided but more commonly becoming 



