NO. 1 TAYLOR: PACIFIC MARINE ALGAE 151 



2. Rhizines chiefly in the central part of the medulla; tetraspo- 

 rangia when young generally regularly placed in rows near the 

 tips of the branchlets ; cystocarps unilocular .... Pterocladia 



2. Rhizines chiefly in the outer or subcortical tissue; tetrasporangia 

 when developing showing young and old stages intermixed ; cysto- 

 carps bilocular, with two pores and groups of carpospores, sepa- 

 rated by a sterile septum Gelidium 



WURDEMANNIA Harvey, 1853 



Plants bushy, often matted or entangled, slender and wirj^, the branch- 

 ing irregular, subalternate ; growth from a small pluriaxial apex, mature 

 structure showing a cylindrical medulla of stout filaments with thick, 

 coalescent walls and a cortex of anticlinal rows of cells. 



Wurdemannia miniata (Draparnaud) Feldmann & Hamel 



Harvey 1853, p. 246; B0rgesen 1915-20, p. 368, figs. 360-361 ; Taylor 

 1928, p. 145, pi. 20, f^gs. 9, 10 (all as W. setacea) ; Feldmann & Hamel 

 1934, p. 17, f^gs. 9-11. 



The figures and descriptions of Feldmann and of B0rgesen show axial 

 filaments with thin walls ; the specimens from Florida seen by the writer, 

 and also the present ones from the west coast of Panama, show thick walls. 

 Harvey's type came from Florida, and Draparnaud's from the Mediter- 

 ranean. Though the differences are slight, it is just possible that two 

 species are involved after all. 



Mexico : Is. Revilla Gigedo, forming tufts under ledges in tide pools, 

 Braithwaite Bay, I. Soccoro, no. 39-52, 18 Mar, 1939. Costa Rica: 

 from below overhanging rocks, Golfo Dulce, no. 39-107, 26 Mar. 1939. 

 Panama: San Francisco, forming scattered sand-covered tufts in tide 

 pools, Panama City, no. 39-140, 31 Mar. 1939. 



GELIDIUM Lamouroux, 1813 



Plants of moderate to small size, cylindrical or flattened, with the axis 

 erect from a somewhat fibrous base, usually laterally branched, wiry to 

 cartilaginous; developing from an apical cell, with ultimately several 

 medullary cell rows and a compact cortex of short radial cell rows, 

 rhizines generally being present in the outer subcortical part of the 

 medulla; tetrapartite sporangia produced in enlargements of the main 



