222 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 3 



Ectocarpus Hancockii sp. nov. 

 Plate 31, Fig. 4 



Frondes 4-6 mm. altae, dense caespitosae; fills erectis non crebro ramosis, circa 

 20 n diam., cellulis 2-3-plo diam. longioribus; gametangiis plurilocularibus later- 

 alibus, sessilibus, 125-175 \x longis, 28-32 n latis, anguste lanceolato-conicis. 



Plants 4-6 mm. high, forming dense tufts on surface of rocks or crus- 

 taceous coralline algae, attached by a mat of cells and basal filaments 

 from which the erect filaments arise abundantly, the latter infrequently 

 branched, about 20 /u, diam., not constricted, commonly blunt-tipped, with 

 cells mostly 2-3 diam. long; plurilocular gametangia abundant, lateral, 

 sessile, 125-175 fi long, 28-32 fi broad, narrowly lanceolate-conical; zo- 

 osporangia unknown. 



Type: D. 133, on rock and crustaceous coralline surfaces, middle 

 littoral, Turner's Island reef off Tiburon Island, Jan. 24, 1940. Herb. 

 AHF no. 8. 



This species differs in several respects from any other known from the 

 Pacific coast. Its small size, saxicolous habit, commonly unbranched fila- 

 ments, and long slender, sessile gametangia are characters which in com- 

 bination mark this plant as very distinct. 



Family Myrionemataceae 

 Genus GOMPSONEMA Kuckuck 

 Gompsonema immixtum S. & G. 



Setch. & Gard., 1924, p. 724, pi. 17, fig. 49; 1925, p. 487. 



J. 58b, growing on Colpomenia sinuosa f. deformans, Isla Partida, 

 July. Not again detected. 



Family Ralfsiaceae 



Genus RALFSIA Berkeley 

 Ralfsia pacifica Hollenberg ms. 



Ralfsia verrucosa Setch. & Gard. (at least in part not of J. Agardh), 

 1925, p. 497. 

 Thallus very dark brown to blackish, 400-800 ju. thick, coriaceous, 

 2-10 cm. in extent, firmly adhering to substratum throughout. The Gulf 

 specimens were examined by Dr. Hollenberg, and, though all are sterile, 

 he finds them satisfactorily referable to this unpublished species. 



