NO. 1 DAWSON: MARINE RED ALGAE OF PACIFIC MEXICO 99 



substrato et inter se laxe affixae, segmentis ultimis aut lobis tantummodo 

 liberis, margines laminae integri, aliquantulum undulati; segmenta terminalia 

 late rotundata expansaque; sori tetrasporangiales late elliptici aut lenticulares, 

 plerasque extermitates segmentorum terminalium latorum occupantes; plantae 

 sexuales non visae. 



Thallus saxicolous, essentially prostrate throughout, forming a 

 mat-like patch 5 cm. or more in extent consisting of 2-3 superimposed, 

 compound, short-lobed, membranous, veined blades with segments 4-6 

 mm. broad, attached loosely to the substrate and to each other by abun- 

 dant rhizoidal pegs with discoid ends, only the ultimate segments or 

 lobes free; blade margins entire, somewhat undulate; terminal seg- 

 ments broadly rounded and expanded; tetrasporangial sori broadly 

 elliptical or lenticular, occupying most of the ends of the broad terminal 

 segments; sexual plants not seen. 



Type: Holotype is E. Y. Dawson 8879, January 2, 1950, in Herb. 

 Beaudette Foundation. 



Type locality: Intertidal, at the end of the Punta Baja head- 

 land, Baja California, Mexico. 



Paratype: Ernst S. Reese BIT-4, Aug. 13-17, 1959, in runoff 

 channel beneath rock wall, blow-hole at Papolote, Punta Banda, Baja 

 Calif. 



Three additional intertidal collections appear to belong here but 

 are sterile and may possibly represent young stages of another species: 

 D. 5961, Santa Cruz Island, Calif.; D. 8773, San Quintin peninsula, 

 Baja Calif.; D. 13358, Punta Thurloe, Baja Calif. 



The type specimen was at first taken to be a juvenile specimen of 

 Cryptopleura lobulifera, but closer examination revealed the distinctive 

 superimposed blades with their ± appressed, short, fertile tetrasporan- 

 gial lobes scarcely free from the prostrate vegetative parts. 



Cryptopleura lobulifera (J. Agardh) Kylin 

 PL 46, fig. 4 

 Kylin 1924, p. 90, fig. 75-76. Neuroglossum lobuliferum J. G. Agardh 1898, 

 p. 121. 



Thalli mostly 5-10 cm. tall, forming a bushy clump on the substrate, 

 purplish-olive, consisting of a group of subdichotomously divided, mem- 

 branous, erect branches whose segments diverge rather widely ; segments 

 8-15 mm. broad, usually with the margins variously crisped and ruffled, 

 the lower portions with a conspicuous midrib and with distinct veins 

 above, the ultimate segments with microscopic veins; tetrasporangial 

 sori lunate to elliptical, restricted to upper portion of segments, lying 

 either just within the margins of segments, or in small, flat, proliferous 

 outgrowths from the segment margins ; spermatangial sori borne in com- 

 pound, crisped marginal lobules; cystocarpic plants not seen. 



Type: A single tetrasporangial plant in the Agardh Herbarium, 

 Lund, Sweden. 



