212 
PACIFIC SCIENCE, Vol. 1 , October, 1947 
Plants in small tufts, epiphytic on other 
algae, or on small sessile animals, filamen¬ 
tous and soft. The determinate branches of 
this species end in three hairs as opposed to 
two terminal hairs in T. macrourum. 
Specimens collected were sterile. 
Keawanui Pond, Molokai Island, with 
Polysiphonia. 
This species is uncommon in this area. 
Reported from the Hawaiian Islands by 
Chamberlain and Papenfuss. 
Polysiphonia Greville, 1824: 90 
Section Oligosiphonia 
Polysiphonia aquamara sp. nov. (see Fig. 
12 a-d). 
Plantae penicillatim fasciculatae, ad 8 cm. 
longitudine sed plerumque minores, roseo-pur- 
pureae, molles, erectae, basi rhizoideis permultis 
praedito nec repente, ramis adscendentibus, alter- 
nis, origine spiralibus. Trichoblasti in articulos 
omnes insertae; cellulae pericentrales 4, haud 
corticatae; tetrasporangia e ramulis secondariis 
ultimis, plantae apicem versus locatis, orta, in 
serie recta vel tortuosa. Plantae cystocarpicae 
validiores, cystocarpis alternis, late urceolatis. 
In Batidem maritimam vel plantas alteras 
phanerogamicas, raro in lapides vel conchas obso- 
letas, crescentes. 
Plants tufted, without a prostrate creeping por¬ 
tion, to 8 cm. in height, usually smaller, reddish- 
purple, soft. Base composed of many rhizoids. 
Erect filaments arise from the base with branches 
ascending, alternate and spiraling in a counter¬ 
clockwise directon, slightly divergent to with 
branching chiefly at the tips. Trichoblasts fre¬ 
quently appearing whorled, inserted in the young 
parts on every segment alternately, in the older 
parts leaving scar cells. The branches of the tri¬ 
choblasts are 2 to 3 ranked, 50-200 m in length, in 
the male plants covering V 3 the length of the tips 
of the axis. Pericentral cells 4, non-corticated. 
Tetrasporangia borne in ultimate branches near 
the tip of the plant, in a straight series or tortu- 
lose, or when in the main branches occasionally 
alternate. Spores dark brown to blackish, sporan¬ 
gia 4-partite, 20 n (usually less) in diameter. 
Antheridial clusters borne on the basal un¬ 
branched portion of a trichoblast, alternate, sub- 
cylindrical, with antheridia blunt to round. Cys- 
tocarpic plants stouter than others, the cystocarps 
alternate, broad urn-shaped, with pyriform carpo- 
spores. 
Type: Abbott 1535- legit C. J. Engard, 
from Station 7, Kuapa Pond, Oahu Island, 
epiphytic on Batis maritima. This number 
includes tetrasporangial, cystocarpic, and 
spermatangial plants, of which I designate 
the tetrasporangial as the type specimen. 
These plants were collected April 7, 1944. 
This new species of Polysiphonia is very 
abundant in the major fishponds, occurring 
on Batis maritima, rocks, and dead shells. 
It resembles P. subtillisima, which has also 
been found outside the strictly marine en¬ 
vironment, but is distinguished from it in 
that it has no prostrate creeping portion. 
Polysiphonia sp. (see Fig. 13). 
A species of Polysiphonia found in fresh 
water (Salt Lake Pond, Oahu); grows abun¬ 
dantly on the pond walls, attached to phane¬ 
rogams, or to rocks. It has four pericentral 
cells. Infrequent trichoblasts are found near 
the tips of the plants. Although repeated 
collections were made, no fertile material 
was found. The salinity in this pond was 
found to be nearly that of fresh water (2.5). 
To the best of my knowledge, this is the 
first report of the genus in fresh water. 
REFERENCES 
Agardh, C. A. Synopsis Algar urn Scandinaviae 
adjecta dispositione universali algarum. xl + 
135 p. Lundae, 1817. 
- Systerna algarum. xxxviii-f -312 p. Lundae, 
1824. 
Agardh, J. G. Species, genera, et or dines al¬ 
garum. vol. 2 (2). 337-700 [+ addenda, 701- 
720] p. Lundae, 1852. 
- Ibid. vol. 2 (3). 701-1291 p. Lundae, 
1863. 
•- Till algernes systematik. Nya bidrag. 
Lunds Univ. Arsskr. 19 (3): 1-177, 4 pi., 1883. 
Areschoug, J. G. Enumeratio Phycearum in 
maribus Scandinaviae crescentium. Nova Acta 
Regia. Soc. Sci. Upsaliensis 13: 1 - 160 , pi. 1-9, 
1847. 
