272 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 12 



Ceramium personatum Setchell & Gardner, prox. 



Setchell k Gardner 1930c, p. 171, pi. 6, figs. 21, 22. 

 Costa Rica: in some abundance on rocks, infiltrated with sand, 

 Port Parker, no. 39-77, 25 Mar. 1939. 



Ceramium affine Setchell & Gardner, prox. 



Setchell & Gardner 1930c, p. 172. 



Ecuador: Guayas, on Gracilaria and other algae from the north- 

 western beach, Pta. Sta. Elena, no. 34-452 (tetrasporangial), 8 Feb. 1934. 



GENTROGERAS Kutzing, 1842 



Plants matted or bushy, filamentous, dichotomously branched and 

 often laterally proliferated ; growth apical, the axis uniseriate, completely 

 corticated by regular longitudinal rows of rectangular cells, the nodes 

 commonly spinulose; tetrasporangia verticillate in the terminal segments 

 of axillary torulose proliferations ; cystocarps lateral, bilobed, partly sur- 

 rounded by short involucral branches. 



Centroceras clavulatum (C. Agardh) Montagne 



B0rgesen 1915-20, p. 241; Taylor 1928, p. 189, pi. 28, figs. 6, 7; 

 1942, p. 123. 



Frequently present in small amounts in shallow-water collections, 

 and no doubt overlooked in some cases in assembling these records, which 

 in general represent cases where this plant was a fairly evident element 

 in the vegetation. 



Mexico: Baja California, intertidal on rocks at Pto. San Bartolome, 

 Bahia Thurloe, no. 34-615, 9 Mar. 1934. Nayarit, attached to surf- 

 beaten rocks of I. Maria INIagdalena, Las Tres Marias, no. 39-634, 9 

 May 1939. Ibid., abundant, forming mats on rocks, I. Isabel, no. 34- 

 5S8B, 5 Mar. 1934. Guerrero, abundant as sandy mats on rocks within 

 reach of the surf, Bahia Petatlan, no. 34-570, 3 Mar. 1934. Oaxaca, 

 common as sandy mats on rocks at Bahia^ Tangola-Tangola, no. 34-549, 

 28 Feb. 1934. Panama : frequent in the higher, hot tide pools at Bahia 

 Honda, no. 39-136, 26 Mar. 1939. Ecuador: Archipielago de Colon, 

 forming mats on rocks exposed at low tide, Pta, Albemarle, I. Isabela, 

 no. 34-112, 12 Jan. 1934. Ibid., I. Rabida, Hassler Exped. no. 1008, 

 Jime 1872. Ibid., among other algae near high tide line. Black Beach 



