NO. 1 DAWSON : MARINE RED ALGAE OF PACIFIC MEXICO 5 



Type locality: On the stalk of a hj^droid {Tubularia sp., prob- 

 ably T. crocea) dredged from a depth of 4 m, on broken shell bottom 

 just inside the entrance of Scammon Lagoon (Laguna de Ojos Liebre), 

 Baja California, Mexico. 



This species differs from others of this genus heretofore reported 

 by its epizoic habit, its irregularly uni- to biseriate filaments, and its 

 open, anastomosing branching. 



Erythrocladia irregularis Rosenvinge 



Rosenvinge, 1909, p. 72-73, figs. 11-12; Kylin, 1925, p. 9, figs. 3a- 

 b; Smith, 1944, p. 166, pi. 37, fig. 1 ; Dawson, 1944, p. 251 ; Doty, 1947, 

 p. 159; HoIIenberg, 1948, p. 156. 



Thalli epiphytic, discoid, unistratose, consisting of irregularly radiat- 

 ing filaments coalesced at the center but free at the irregular margins, 

 forming an adherent plate 50-300 /a in diameter; marginal cells elongate, 

 not bifurcate; asexual reproduction by subspherical monosporangia cut 

 of? from cells of the central part of the disc. 



Type: Holotype not designated. A syntype of Rosenvinge XO 

 8/8/99 is under accession number 6574 in the Botanical Museum, Uni- 

 versity of Copenhagen, Denmark. 



Type locality: Epiphytic on Polysiphonia urceolata in depths of 

 11-15 m., M^llegrund, about ^ mile off Hirshals, north Denmark. 



Mexican distribution: Gulf of Calif. — D. 718-40, epiphytic on 

 Dictyota, Isla Turner, Sonora, July. 



Erythrocladia subintegra Rosenvinge 



Rosenvinge, 1909, p. 73-74, figs. 13-14; Kylin, 1925, p. 9, figs. 3c- 

 g; Smith, 1944, p. 166, pi. 36, fig. 6; Dawson, 1944, p. 251 (without 

 name heading) ; Dawson 1945b, p. 65; Doty, 1947, p. 159; HoIIenberg, 

 1948, p. 156. Erythrocladia polymorpha Howe, as interpreted by Setchell 

 & Gardner, 1924, p. 741. 



Thalli epiphytic, discoid, unistratose, consisting of more or less co- 

 alesced, regularly radiating filaments forming a thin plate 50-300 /x in 

 diameter or more, the margins of the disc subentire with many bifurcat- 

 ing cells; asexual reproduction by subspherical monosporangia about 15 

 /A in diameter cut off from vegetative cells in the central part of the disc. 



Type: Holotype not designated. A syntype of Rosenvinge XO 

 8/8/99 is under accession number 6574 in the Botanical Museum, Uni- 

 versity of Copenhagen, Denmark. 



