400 
(11089); epiphytic on Codium, Sta. 3 (11208). 
B0rgesen has discussed this species at 
length and shown that it is a widespread and 
variable plant of warm seas, having been de- 
scribed and illustrated under many different 
names. The Nha Trang specimens show con- 
siderable variability, some being saxicolous, 
others epiphytic. The discoid chromatophores 
and sessile, terminally acute, plurilocular spo- 
rangia are characteristic. Figure 14^ is virtually 
identical with Weber van Bosse’s figure 36 
(1913) of an epiphytic plant from Indonesia 
which B0rgesen has identified as Ectocarpus 
irregularis. 
Ectocarpus mitchellae Harvey 1852: 142, 
pi. 12 G (Massachusetts); B0rgesen 1941: 
7, figs. 1-5 ^ 
LOCAL DISTRIBUTION: Forming tufts to 2.5 
cm. high on intertidal rocks: Sta. 8 (11269); 
Sta. 1 (11087); Sta. 2 (11301). 
The presence of unilocular as well as plu- 
rilocular sporangia in 11087 is in accord with 
the Mauritius plants studied by B0rgesen. 
The plurilocular sporangia in 11269 are gen- 
erally somewhat tapered, as in his figure la, 
and as generally found in this species, while 
those of 11301 are longer, more blunt, and 
cylindrical, as seems to be more characteristic 
of Ectocarpus indicus Sond. Yet they are like 
his figure lb. 
Mesospora schmidtii Weber van Bosse 
I9IO: 27 (Indonesia); Weber van Bosse 
1913: 143, fig. 43, pL 2, figs. 2, 3 
Fig. 14/, m 
LOCAL DISTRIBUTION: Abundant, forming 
a dark-brown film, very slippery when wet, 
over large areas of high, exposed rocks, Sta. 
1 (11074). 
The films are about 200 fi thick, composed 
of densely compacted, erect filaments as in 
Figure 14/. In January these were producing 
unilocular sporangia abundantly, but pluri- 
locular sporangia were not seen. 
PACIFIC SCIENCE, Vol. VIII, October, 1954 
Ralfsia sp. 
A few limpet shells are present in the col- 
lections from Sta. 9 which bear crusts of a 
species of Ralfsia. These show ascending rows 
of compact, -f — angular cells terminating 
in paraphyses which bear immature plurilocu- 
lar sporangia. The material is not suitable for 
identification.but indicates the presence of the 
genus. 
Sphacelaria novae-hollandiae G. Sonder 
1845: 50 (West Australia); B0rgesen 1941: 
45, fig. 20a-d; Taylor 1950: 97 
Fig. 14g 
LOCAL DISTRIBUTION: On coral fragments, 
Sta. 7 (11244). 
The propagulae are about 100 fj, long and 
have the corner cells divided by a wall into 
two superimposed halves. The plants are ap- 
parently identical with those of Taylor from 
Bikini and of B0rgesen from Mauritius. 
Sphacelaria furcigera Kiitzing 1855, Tab. 
Phyc. 5, pi. 90, fig. 2 (Karak Island, Persian 
Gulf); Bprgesen 1941: 46, fig. 21 
Fig. I4h 
LOCAL DISTRIBUTION: Forming low, dense 
tufts less than 1 cm. high on rocks, Sta. 11 
(11414). ' 
Sphacelaria tribuloides Meneghini 1840: 2, 
No. 6 (Dalmatia); Vickers 1908, part 2, 
pi. 26; Bprgesen 1941: 41, fig. 18a-c 
Fig. 14/, j 
LOCAL DISTRIBUTION: Forming dense tufts 
about 1 cm. high on non-coral rocks, Sta. 2 
(11088). 
Pocockiella variegata (Lamx.) Papenfuss 
1943: 467, figs. 1-14. Dictyota variegata 
Lamouroux 1809/^: 331 (Antilles). Zonaria 
variegata (Lamx.) C. Agardh 1817: xx 
Fig. \4k 
LOCAL DISTRIBUTION: Frequent on coral 
fragments in shallow water to 3 m., Sta. 1 
