304 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 12 



Pterosiphonia dendroldea (Montagne) Falkenberg 



Plate 96, Fig, 2 



KyHnl941,p. 39. 



These specimens, particularly those from Academy Bay, are very 

 large and fine, reaching a height of 15-18 cm, but are sterile. Micro- 

 scopically they agree closely with Phyc. Bor.-Amer. no. 462. 



Mexico: Baja California, dredged ofi Pt. Hughes on Cabo San 

 Lazaro, no. 34-604, 7 Mar. 1934. Near Is. Revilla Gigedo, Albatross 

 Exped. no. 8, sta. 2836, 4 May 1888. Ecuador: Archipielago de Colon, 

 growing on Sargassum south of Banks Bay, I. Isabela, no. 34-132, 13 

 Jan. 1934. Ibid., abundantly dredged off Academy Bay, I. Santa Cruz, 

 no. 34-320, 20 Jan. 1934. Ibid., rare at Black Beach Anchorage, I. 

 Santa Maria, no. 34-228, 17 Jan. 1934. Ibid., dredged from 55 meters' 

 depth off Post Office Bay, no. 34-377, 29 Jan. 1934. 



Pterosiphonia Baileyi (Harvey) Falkenberg 

 Harvey 1853, p. 29 (as Rytiphlaea Baileyi). 



Mexico : Baja California, one specimen secured at South Bay, I. 

 Cerros, no. 34-629 (cystocarpic), 10 Mar. 1934. 



LOPHOSIPHONI A Falkenberg, 1897 



Plants filamentous, the primaiy axes creeping and attached by rhi- 

 zoidal holdfasts, cylindrical, laterally branched, dorsiventral with the 

 apex at first recurved ; erect filaments of limited growth, very sparingly 

 branched, the apices sometimes recurved and bearing on the convex side 

 a series of deciduous trichoblasts ; tetrasporangia formed in the upper 

 branches of somewhat more freely divided filaments. 



Lophosiphonia villum (J. Agardh) Setchell & Gardner 

 Setchell k Gardner 1903, p. 329; Kylin 1941, p. 40. 

 Costa Rica: plants forming mats tightly attached to rocks in the 



deeper tide pools, Golfo Dulce, no. 39-115, 26 Mar. 1939 (det. G. J. 



Hollenberg). 



HERPOSIPHONIA Nageli, 1846 

 Plants delicate, creeping, with a slender branching rhizomatous axis 

 attached by haptera with disk-shaped ends, the apex commonly recurved, 

 the dorsal side with determinate simple erect branchlets terminating in a 

 tuft of trichoblasts; axis and erect branchlets regularly polysiphonous, 

 ecorticate; tetrasporangia in a series in the erect branchlets; pericarps 

 oval to globose, subterminal or lateral on the erect branchlets; sperma- 

 tangia pedicellate near the tips of the erect branchlets. 



