NO. 1 DAWSON : MARINE RED ALGAE OF PACIFIC MEXICO 17 



the apical part of the blade ; carpospores in packets of 8 according to the 

 formula 1, 1., L, in a continuous bright rose marginal zone on either side 



a b c 



of the blade and including the apical region. 



Type: Holotype is Dawson 982a, Feb. 22, 1946 ,on sheet 4117, 

 including slide 878 and vial 1635, in HAHF. 



Type locality: On shaded cliff rocks in the spray zone, growing 

 with Porphyra thuretii, Isla Partida, Gulf of California. 



Additional material: A few small blades of this species were 

 found with Porphyra thuretti at Isla Patos, Sonora (D. 726a, Feb. 

 1946). 



This species is similar to Porphyra linearis Grev. but is marginally 

 strongly ruffled unlike that species. It differs from P. pseudolinearis 

 Ueda in having only 8 carpospores per packet instead of 32. 



Porphyra perforata J. Agardh 



J. Agardh, 1883, p. 69, pi. 2, figs. 62-64; Smith, 1944, p. 172, pi. 39, 

 fig. 5; Hus, 1902, p. 202-207, pi. 20, figs. 4a-10; Dawson 1945b, p. 60; 

 Dawson 1949, p. 225 ; Doty, 1947, p. 161. 



Thalli saxicolous, membranous, up to 30 cm. high, usually brownish- 

 purple in color, sessile, with a small disc-shaped holdfast, consisting of a 

 single irregularly shaped blade about as broad as long, deeply ruffled and 

 often lobate or laciniate; blade monostromatic, 45-75 fx thick, the cells 

 ellipsoidal, 40-100 /x tall, each with a single stellate-reticulate chromato- 

 phore more or less filling the cell, and one pyrenoid ; plants monoecious, 

 the spermatangia and carposporangia in patches along the thallus mar- 

 gins; spermatia in packets of 128 according to the formula 1, 1,?. ; car- 



a b c 



pospoies in packets of 32 according to the formula i , 1, -. 



a b c 



Type: Holotype not designated. Syntypes of Lyall, Berggren, and 

 Bingham are in the Agardh Herbarium, Botanical Museum, University 

 of Lund, Sweden. 



Type locality: *'In oceano pacifici superiore ad Californiam," 

 but specimens from Santa Barbara and from San Francisco, California 

 were illustrated. 



Mexican distribution: Pacific Baja Calif. — Cooper 536, Playa 

 Rosarita, Mar.; D. 160, Jan., D. 5236, Sept., Cabo Colnett; D. 9641, 

 Punta San Quintin, Apr.; D. 8687, Jan., D. 1276, Apr., Punta Baja; 

 D. 1619, Punta Maria, Apr.; D. 1448, Punta Santa Rosalia, Apr.; D. 

 9061, Apr., D. 9402, May, Islas San Benito; Osorio-Tafall, Sept. 1, 

 1946, Isla San Roque; D. 9160, Bahia Asuncion, Apr.; D. 9268, Isla 

 Magdalena, May. 



