266 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 17 



of the blades, mostly in the region of the ultimate dichotomies, cruciate, 

 30-36 ju, long, 15-18 /A wide; gonimoblast developing from an auxiliary 

 cell situated in a system separate from that bearing the two-celled carpo- 

 gonial branch; cystocarps embedded in the blade on either side, aggre- 

 gated in the central areas of the upper segments, 200-300 /* in diameter, 

 causing a bulging of the blade-surface, ostiolate, consisting at maturity 

 of a dense mass of carpospores pedicellate on the old auxiliary cell, the 

 whole surrounded by a rather thin sterile envelop of slender filaments; 

 antheridia superificial in an indefinite, sub-nemathecial sorus on upper 

 branches in the region of the utimate dichotomies. 



Type: Holotype not designated. Syntypes, cited as collections of 

 Mrs. Bush, Mr. Cleveland and Mrs. Snyder, are in the Farlow Herb- 

 arium, Harvard University, Cambridge, Mass. Mrs. Snyder's collections 

 distributed as ^ 600 in Phycotheca Boreali-Americana may be con- 

 sidered syntypes. 



Type locality: Not designated, but the syntypes came from San 

 Pedro and San Diego, California. 



Mexican distribution: Pacific Baja Calif. — D. 10285, near the 

 mouth of Rio San Miguel, Aug.; D. 1519, Punta Santa Rosalia, Apr.; 

 D. 10522, Punta Norte, Isla Cedros, Oct. ; Taylor 34-647, Bahia Sur, 

 Isla Cedros, Mar.; D. 10034a, Punta Velero, Apr.; D. 10369, Punta 

 San Eugenio, Nov.; D. 9063, Apr.; D. 9436, May, Islas San Benito; 

 D. 9133, Apr., Osorio-Tafall, Sept. 1, 1946, Bahia Asuncion; D. 9485, 

 Punta Abreojos, Apr. 



This plant agrees in structure and reproduction with the type species. 

 Poly opes constrictus (Turn.) J. Ag. from Australia, as illustrated by J. 

 Agardh 1879, pi. 6, figs. 1-11. However, there is also reason to recognize 

 a very close relationship between this species and the northeast Pacific 

 species of Zanardinula. One must await critical monographic studies for 

 a suitable circumscription of these two genera and for a clarification of 

 any differences between them which may be real. 



Polyopes bushiae is an inhabitant of the upper sublittoral and may 

 normally be collected in its shaded habitats under overhanging ledges 

 only at times of exceptionally low water. 



Polyopes clarionensis Setchell & Gardner 



Setchell and Gardner 1937, p. 91, pi. 4, fig. 9, pi. 6, fig. 17, pi. 23, 

 fig. 45. 



