84 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 26 



plant grows. See also S. pinnata for similar responses demonstrated by 

 collections from the Gulf of California. 



Sorella pinnata Hollenberg 

 PL 38, fig. 1; PI. 40, fig. 6 

 Hollenberg 1943, p. 578, fig. 15-16; Dawson 1944, p. 321, pi. 47, fig. 3-4; 

 Dawson 1951, p. 53. 



Thalli 1-2 cm. tall (or up to 7 cm. in luxuriant examples), rose pink 

 in color, semi-prostrate in inferior parts, the segments membranous, 

 lanceolate, 0.5-2 mm. (sometimes to 3.5 mm.) broad, with acute, 

 obovate to lanceolate, irregularly pinnate branchlets and dentae, with an 

 inconspicuous midrib, monostromatic except at the midrib and in lower 

 parts; growth from an apical cell, the primary cell row with intercalary 

 division; margins minutely denticulate; tetrasporangial sori 300-400 

 (800) [x in diam., oval, solitary in the middle of branches near the 

 tips; cystocarps 400-500 ll in diam., on one side of the midrib, with a 

 single pore; spermatangial sori oblong, 150-200 jx in diam., mostly in 

 pairs, one on either side of the midrib and often several pairs oc- 

 curing on a single branch. 



Type: Hollenberg 3921, Nov. 7, 1942, in the herbarium of G. J. 

 Hollenberg, University of Redlands, Calif. 



Type locality: On intertidal rocks, Laguna Beach, Orange Co., 

 Calif. 



Mexican distribution: Pacific Baja Calif. — D. 8011, Cortez 

 Bank, 30-40 m.; D. 4225, Isla Coronado del Norte; D. 10564, Isla 

 Cedros; D. 9421, Islas San Benito; Gulf of Calif. — D. 856, Isla Jorge; 

 D. 194-40, Puerto Refugio, Isla Angel de la Guarda; D. 666, Puerto 

 Libertad (growing luxuriantly (to 7 cm. tall) with Branchioglossum 

 woodii in the subtidal, and of similar habit) . 



Grinnellia lanceolata Dawson 



PI. 39, fig. 5 

 Dawson 1944, p. 322, pi. 47, fig. 6. 



Thalli 2.5-6 cm. tall, consisting of several short-stipitate blades from 

 a minute, pulvinate or discoid holdfast; blades lanceolate at first, 6-8 

 mm. wide, expanding to 2-3 cm. wide, monostromatic except at the 

 delicate midrib, undivided, without side nerves, with entire, only slightly 

 undulate margins, the apices blunt, with an apical cell ; primary cell row 

 without intercalary divisions; tetrasporic sori scattered over blades on 

 either side of midrib, tending in part to be oriented in faintly decussate 

 rows; spermatangial sori irregular, angular, 50-500 /x in extent, 

 scattered over blades; cystocarps scattered over the thallus, up to 1 mm. 

 in diam., seeming to have a small scale-like projection on one side, but 

 this actually representing the tip of the fertile leaflet on the midrib of 

 which the procarp develops (very young cystocarps project downward 



