Brackish-Water Algae from Hawaii— Abbott 
similarity to variety typica than do our specimens 
to any of these. Boergesen (1946: 341) has raised 
B. Harveyana to specific rank. Setchell’s B. Har¬ 
veyana of Samoa (1924) and Tahiti (1926) 
should not be included in synonymy with B. 
plumosa var. Harveyana, as those specimens are 
quite different from Boergesen’s specimens. 
It is obvious from the literature that there is 
great confusion as to species limits in this genus. 
Lacking critical specimens, I am following the 
interpretation of Taylor (1928) and of Collins 
and Hervey (1917). At best, this practice is not 
too satisfactory, as the Pacific plants by and large 
are somewhat different from the Atlantic and 
Caribbean forms. A large suite of specimens and 
comparison with type material are desirable. 
Br y op sis plumosa has been reported from the 
Hawaiian Islands by Chamberlain, Tilden, and 
MacCaughey. I have examined the Tilden speci¬ 
men (453) in American Algae Century V 
(190l£), and find it to be identical with ours. In 
all probability, the records are in agreement with 
the material mentioned here. 
Caulerpa Lamouroux, 1809^: 136 
Caulerpa Sertularioides (Gmelin) Howe in 
Torrey Bot. Club Bui. 32: 576, 1905. 
Plants to 4 cm. in height, creeping parts 
clinging tightly to sand and rock particles, 
the upper portions flattened laterally, with 
opposite or nearly opposite "leaflets.” 
At one station, adjacent to the main 
regions of Kuapa Pond, near the connections 
to the sea. 
The genus is common in marine habitats 
in the Hawaiian Islands; this species and one 
related closely to it are among the more 
prominent members of the genus in Hawaii. 
Reported from the Hawaiian group by 
Eubank (1946). 
PHAEOPHYCEAE 
Ectocarpus Lyngbye, 1819: 130 
Plants tufted, filamentous, arising from a 
single basal cell, or from a group of cells, 
with or without rhizoids at the base, attached 
to twigs, wood, or other algae. Plants in 
this series to 6 cm. in height, but more 
usually 1-2 cm. Reproduction by plurilocu- 
lar or unilocular sporangia. 
199 
In the sense of Hamel (1939: 66-67) 
the species which is described below would 
more properly fit in the segregated genus 
Feldmannia, which differs in a few char¬ 
acters—mainly in that it has discoid chro- 
matophores, whereas the limits of Ectocarpus 
are such as include only those members of 
this complex which have ribbon-like chro- 
matophores. 
One of the characters used to separate 
Feldmannia further is the strong ramifica¬ 
tions of filaments near the base, a character 
not shown by our plants. Sporangia are typ¬ 
ically pedicellate in Feldmannia, a condition 
only infrequently occurring in our speci¬ 
mens. 
Giffordia, in the sense of Hamel, is char¬ 
acterized by discoid chromatophores also, 
but sporangia are always sessile, and the 
plant has intercalary growth. These are not 
constant characters in our plants. 
It would thus seem best to retain the spe¬ 
cies below in the genus Ectocarpus, sensu 
latiore, until European workers who have 
authentic material can establish further char¬ 
acters for the separations so badly needed in 
this complex. 
In making a survey of literature pertinent 
to Hawaiian material, some confusion was 
encountered with Ectocarpus Duchassaingia - 
nus Grunow (1870), recorded for the Pa¬ 
cific from Samoa (Setchell, 1924). From 
the literature, this species seemed identical 
with Ectocarpus indie us Sonder, recorded 
earlier by Weber-van Bosse (1913: 129) 
from Malaya. The writer has examined ma¬ 
terial used by Setchell in his study, and has 
concluded that his plants are synonymous 
with E. indicus Sonder. 
When these studies were completed, re¬ 
prints of Boergesen’s instructive Mauritius 
papers were received, and it was interesting 
to find that he had come to the same conclu¬ 
sions regarding E. Duchassaingianus, which 
he based on specimens from the Danish 
West Indies (Virgin Islands). 
