62 ALLAN HANCOCK PACIFIC EXPEDITION* VOL. 26 



above (15-20 jx) gradually lengthening to about 100 (200) jx; apices 

 forcipate, provided abaxially with a series of sharp, 3-4-celled, straight 

 or recurved, partially deciduous spines, 30-50 p. long; tetrasporangia 

 abaxial, tending to become whorled, involucrate by bracteate filaments, 

 prominent, causing the nodal band to appear tumid, ovoid, about 40 

 jx in diam.; spermatangia in low, pulvinate, mostly adaxial masses at 

 nodes; cystocarpic plants not seen. 



Type: A collection by M. K. Nemoto in the Okamura Herbarium, 

 Faculty of Sciences, Hokkaido University, Sapporo, Japan. 



Type locality: Kamahara, Iwaki Province, Japan. 



Mexican distribution: Pacific Baja Calif. — D. 8544, Isla 

 Guadalupe (This plant exhibits exceptionally long spines (110 /x) of 

 5 cells plus 1 or 2 small lateral cells at the base; they are straight 

 and occasionally forked, not particularly seriate and usually persis- 

 tent.) Gulf of Calif.— D. 18578-9, Isla San Pedro Nolasco; D. 1980, 

 3522, Drouet & Richards 3408, vie. of Guaymas; D. 3237, Punta 

 Palmilla; D. 6810, Cabeza Ballena; D. 3637, Mazatlan. Oaxaca—D. 

 10752, Salina Cruz. 



Ceramium personatum Setch. & Gard. 



PL 29, fig. 3-4 



Setchell & Gardner, 1930, p. 171, pi. 6, fig. 21-22; Dawson 1950 p. 133. 



Thalli 8-15 mm. high, 110-120 /x in diam. below, diminishing 

 gradually toward the apices; branching dichotomous, the tips slightly 

 incurved, corticated only at the nodes, the nodal bands narrow, about 

 1/2 as high as wide or less, slightly higher in lower segments than 

 upper, very slightly projecting beyond the internodal cells, with even 

 margins above and below, with large cells below and smaller ones 

 above the center, some of the larger cells in older parts giving rise to 

 descending pluricellular rhizoidal appendages against the internodal cell 

 walls; internodes shorter above, 2 times the breadth below; tetraspor- 

 angia projecting, somewhat immersed or fully naked, at first abaxial, 1-2 

 at a node, later whorled and somewhat involucrate, 75-85 /x long, 

 somewhat caudate ; spermatangia in adaxial, pulvinate tufts at the nodes, 

 tending to become whorled; cystocarps unknown. 



Type: H. L. Mason 83, April, in Herb. California Academy of 

 Sciences (173622) 



Type locality: Epiphytic, Isla Guadalupe, Mexico. 



Mexican distribution: Pacific Baja Calif. — D. 13453 Bahia 

 Magdalena. 



Setchell and Gardner recognized certain similarities between this 

 plant and their earlier described C. caudatum. I have noted this also 

 and suggest that C. personatum may utimately prove to be a variant of 

 C. caudatum. The pluricellular rhizoidal appendages are conspicuous 



