80 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 26 



cell row and the similar, parallel, basal cells of the secondary cell rows; 

 cysocarpic and tetrasporic plants not seen. 



Type: Dawson 755a, Feb. 18, 1946, in Herb. A. Hancock 

 Foundation (43230). 



Type locality: On intertidal rocks in crannies, northeast side 

 of Isla Patos, Gulf of California, Mexico. 



This species is distinguished from others of the genus by its tufted 

 habit and typically unbranched, blunt-spatulate blades which, compared 

 to other species of Membranoptera, are relatively broad with respect to 

 length. 



Holmesia calif ornica (Dawson) Dawson 

 PI. 35, fig. 6-7; PL 36 

 Dawson 1945b, p. 96. Loranthophycus californicus Dawson 1944, p. 655, 

 fig. 1-4. 



Thalli erect, membranous, to 12 cm. high, rose colored, attached 

 to rocks by a thin, adherent crust augmented by a few short clasping 

 stolons, expanded from a branched, subterete stipe 1.0-1.5 cm. high; 

 blades 3-4 from each main stipe, narrowly cuneate for 1.5-2.0 cm. above 

 the point of branching, then expanding abruptly into a thin, smooth, 

 veinless, narrow-ovate, membranous portion 3-4 cm. broad, this usually 

 simple, but sometimes divided above the middle; margins irregularly 

 shallowly lobed or undulate; transection showing an external layer of 

 small, flattened, pigmented, rectangular cells and several irregular 

 medullary layers of large, colorless, thin-walled cells; tetrasporangia 

 borne in special fertile branchlets from the surface of the membranous 

 blades; fertile branchlets 1-2 mm. long, simple or forked, compressed, 

 acute, 400 p broad, 200 p thick, from a cylindrical base; tetrasporangia 

 scattered, 90-100 p in diam.; sexual plants not seen. 



Type: A collection by Martin W. Johnson, Mar. 10, 1944, in 

 Herb. University of California, Berkeley. 



Type locality: Dredged from a rocky bottom at a depth of 25 

 meters off Point Loma, San Diego, Calif. 



Mexican distribution: This species has been reported now from 

 much of the Pacific Coast from Washington State to southern California 

 (a recent collection is Dawson 5808, at 41 m., off Santa Cruz Island), 

 and, since the type came from very near the Mexican boundary, 

 may be expected in moderate depths along the northwest coast 

 of Baja California. 



Schizoseris pygmaea Dawson 



PL 35, fig. 3-4 

 Dawson 1950a, p. 157, fig. 16-17; Dawson 1959, p. 29. 



Thalli 1-2 (3) cm. high or more, from a discoid base, or the base 

 a ± prostrate, terete structure with rhizoidal attachments, consisting of 

 one to several irregularly, dichotomously branched or lobed monostroma- 



