412 
PACIFIC SCIENCE, Vol. VIII, October, 1954 
Goniotrichum humphreyi Collins 1901: 
251 (Jamaica); Tanaka 1952: 8, fig. 4 
Fig. 25b, c 
LOCAL DISTRIBUTION: Growing with En- 
teromorpha on upper rocks, Sta. 10 (11328). 
This plant consists of a slender, unbranched 
or slightly branched filament which is uni- 
seriate at the base and attached by a slight 
enlargement of the gelatinous base of the 
filament, either with or without enlargement 
of the cavity of the lowermost cell. The fil- 
aments are about 15 m in diameter near the 
base and 30-35 m thick above. 
Erythrotrichia parietalis Tanaka 1952: 18, 
fig. lOa-e (Hyuga Prov., Japan) 
Fig. 25d, e 
LOCAL DISTRIBUTION: Epiphytic on Hypnea 
esperi from coral rocks, Sta. 2 (11079). 
My material corresponds closely with Ta- 
naka’s figures of this newly described plant. 
The parietal chromatophore and the penetrat- 
ing basal cell are distinctive. The filaments are 
about 10-20 11 in diameter. 
Porphyra crispata Kjellman 1897: 15, pL 1, 
figs. 4, 5, pi. 3, figs. 5, 6, pi. 5, fig. 15 
(Japan); Tanaka 1952; 34, pi. 4, figs. 2, 3, 
text fig. 17A-Q 
Fig. 24 
LOCAL DISTRIBUTION: Epiphytic on Gym- 
nogongrus, Sta. 6 (11220). 
My plants are sterile but up to 2.5 cm. tall 
and in full agreement vegetatively with this 
species known from Formosa and the Ryukyu 
Islands. The thallus is monostromatic and 
provided with minute marginal teeth. The 
species is said to grow on rocks in Japan. 
Key to the Species of Acrochaetium 
1. Basal attachment by a single cell 
A. robustum 
Basal attachment by several to many 
cells 2 
2. Basal cells at least partially penetrating the 
host. 3 
Basal cells not penetrating the host. . . .4 
3. On Ltagora\ attached by penetrating fil- 
aments A. occidentale 
On Pterocladia', attached by a disc with 
only slightly penetrating cells .......... 
A. subseriatum 
4. About 200 fi high; monospores unilateral 
A. sancti-thomae 
To 1.2 mm. high; mono spores multifari- 
ous A. gracile 
Fig. 24. Porphyra crispata: Habit, X 0.9. 
Acrochaetium sancti-thomae B0rgesen 
1915: 30, figs. 23, 24 (Virgin Islands on 
Sargassum) 25 ^-. 
LOCAL DISTRIBUTION: On ChuetoMorpha an- 
tennina, Sta. 8 (11265). 
These plants reach a little over 200 ji in 
height and are in good accord with this West 
Indian species. In habit they are particularly 
like B0rgesen’s figure 23c. The filaments, 
however, are somewhat more slender (about 
6 )u) than described for this species (8-9 m)- 
Hairs are common. Although not mentioned 
by B0rgesen, germinating spores show a divi- 
sion into two cells which remain distinct for 
a time from other cells of the basal filaments, 
as in Kylinia pulchellum and K. dubosquii. Un- 
