Polysiphonia of Tropical Pacific — Hollenberg 
205 
This species resembles P. fragilis Suringar as 
interpreted and figured by Okamura (1929, 
Vol. VI: PL 255, figs. 1-15). However, Oka- 
mura describes trichoblasts as arising one per 
segment. Segi (1951:251, as P. forcipata Har- 
vey) describes and figures a similar plant with 
trichoblasts on every segment. P. pentamera also 
resembles P. polyp hysa Kutzing, collected by 
Vieilard in New Caledonia, and figured in Kut- 
zing (1863, Vol. 13:20). P. polyp hysa is de- 
scribed as having 5 pericentral cells and very 
short segments, but the branch apices are de- 
scribed as forcipate, and the pericentral cells 
as "valde inflatis.” 
Polysiphonia tepdia Hollenberg 1958:65 
P. flabellulata of Menez 1964:219, (non P. 
flabelhilata Harvey 1860:330); ?P. denu- 
data Taylor (I960) as concerns non-corti- 
cated forms 
Fig. 3 D, 3 E 
Plants 1-8 cm high, very soft and flaccid, 
assurgent from a brief prostrate base attached 
by numerous unicellular rhizoids, which are cut 
off by a cross-wall mostly from the proximal end 
of the pericentral cells, which may have digi- 
tate tips and may be as much as 1.3 mm long; 
pericentral cells mostly 7, sometimes 6 in upper 
branches, or 8 at the base, ecorticate, with seg- 
ments in median parts of main erect branches 
mostly 1-1.5 diameters long and 140-2 5 Op in 
diameter; walls thin and hyaline or thick and 
stratified in lower parts; main axes not promi- 
nent, branching pseudodichotomously at wide 
angles up to 45 degrees below, at very narrow 
angles and somewhat distichous in upper parts, 
! with 4-10 or more, but mostly 8, segments be- 
tween successive branches; branches arising in 
connection with trichoblasts; trichoblasts com- 
monly 1-2 between successive branches, often 
poorly developed, but sometimes well devel- 
oped, 200-5 OOp long and with 2-3 forks and 
delicate tips, mostly soon deciduous, leaving 
small scar-cells; tetrasporangia 50-70-(95)p in 
diameter, in short or longer straight series in 
the ultimate and subultimate ramuli; cystocarps 
subglobose and about l60p in diameter, accord- 
i ing to Menez (1964:219). I observed only 
I immature cystocarps; spermatangial branches not 
1 observed in the material examined, but de- 
scribed by Menez as arising as a primary branch 
of a trichoblast. 
type locality: Beaufort, North Carolina, 
United States mainland. 
COLLECTIONS examined (all from the Ha- 
waiian Islands) : D. 9765 A, tetrasporic, near 
the Army Gate, Sand I., Oahu, Jan. 27, 1952; 
D. 18020, tetrasporic, cystocarpic, Kaneohe Bay, 
Oahu, Oct. 10, 1953; D. 19756, tetrasporic, 
scraped from the hull of a boat in Ala Wai 
Yacht Harbor, Honolulu, Oahu, Nov. 14, 1951; 
H. 62-12, from an aquarium of sea water in 
which fish were being reared and fed the Poly- 
siphonia for food, Sans Souci Beach Laboratory, 
Waikiki, Oahu, Dec. 3, 1962; an unnumbered 
collection, by I. A. Abbott, from Keawanui 
Pond, Molokai, Aug. 24, 1944. 
A plant described and figured by Boergesen 
(1918:269, figs. 263, 264) may be P. tepida, 
although Boergesen’s fig. 264 shows rhizoids in 
open connection with the pericentral cells. 
Polysiphonia tsudana sp. nov. 
Polysiphonia sp. of Tsuda 1965:21 
Figs. IF, 1 G, 2 C 
Prostrate branches 40-62 p in diameter, com- 
posed of segments about 1 diameter long, at- 
tached by unicellular rhizoids, which are cut 
off by a cross-wall from the center or distal end 
of the pericentral cells; erect branches arising 
mostly cicatrigenously at close but irregular 
intervals, to 4 mm high and 45-50p in diam- 
eter, mostly unbranched, with segments 1 
diameter long or less; pericentral cells 4 in the 
prostrate branches, 6-9 in erect branches, about 
the same size as the central cell, ecorticate, com- 
monly of unequal length in a given segment 
and not strictly in longitudinal rows; tricho- 
blasts infrequent and very rudimentary, but pri- 
mordia (or scar-cells) commonly one per 
segment and in mostly 14 spiral sequence, ex- 
cept in tetrasporangial branches where they are 
unilateral; tetrasporangia about 36p in diameter, 
one per segment in short, non-spiralling series, 
somewhat distending the segments; spermatan- 
gial branches (immature) lanceolate, to 65 p 
long, apparently without a sterile tip, on a very 
short, 1 -celled pedicel, arising from the entire 
trichoblast primordium; cystocarps unknown. 
