Jap.J.Phyco.
l(Sorui)28:1
65‑
167.September20，1980

TheoccurrenceofZonarias
tipitataonthesouthern coastsofTaiwan
Young‑Meng CHIANG and Hong‑Nong CHOUInstitut
eofOceanography，NationalTaiwan Univ
ersi
むら T
aipei，
Taiwan，Rφubli
cofChina，

ZonariastipitatawaserectedbyTANAKAand NOZAWA in 1962based on thespeci‑，a smallmens collectedat Tanegashimaislandsituatedatthe southwestern part，ofJapan. This brown algai
satropicalsubtropical to warm temperate， deepwater species found inthe southwestern，Ryukyu Islands(TANAKAislandsofJapan
andNOZAWA1
962)，SouthVietnam(TANAKA969) and Guamand NOZAWA 1962，Ho 1(TSUDA 1972).
Duringthreeindependentdiv
ingsurveys
on the southern partof Taiwan by Dr.
・MING CHEN ofthe Department ofYINGGeology，National Taiwan University，atSiaoliuchiuIsland on September 9，1972
andMr.C.S. CHENandMiss J.E. LEWIS， Academiaof the Institute of Zoology，Pingtong Hsien onSinicaat Wanlitung，1977 and Lanyeu Island onFebruary 1
9December12，1979respectively，manyspeci‑mens ofthis brownalg
awerecollectedatenttot
hedepths of5t
o20meters and sw
riter
s. Subsequent examinations ofthethallishowedthattheypossesssomechar‑acters which had not been mentioned int
heor
igina
lde
scr
i
pt
ion
so
r elsewhere ofthisalg
a. The plant
sat handreach5cmer
ennialfeltedrhi‑high，growingfrom ap
zoidalbasewhichi
supto1cmacr
ossand0.
5cm i
nt
hi
c
kness. From the base arisesev
eralc
yl
indr
ical，sl
ende
rs
tal
k
supt
o1.5cm hi
gh. Stal
k
sar
eu
suall
y simple butmayoccasionall
ygiv
er
i
set
o form one toafewl
aterals. They are smooth atfirst，laterusuall
ybecomingcoveredwithmany
brown hairs. The stalki
s composed ofcomparativelyt
hick‑walledcells which aresubsphericalt
o polygonal i
nt
hec
or
t
i
cal

・
regionand c
yl
indr
icali
n the medianpor

tlOn.

Fromthetopo
feachstalkarisesamem‑
branous blade. The blade is fan‑shaped，laterbecominglobed or laciniateatfirstby splitting. Both sur
facesof the bladear
e u
suall
y smooth; neither concentr
ic
bands o
fh
air
snorv
ei
n
sar
epr
esent. Butinsomemature blades，therear
e rows ofbrown hairs on the abaxialsideof thebladeextendingfrom theb
asa
lpor
t
io
ntothe upperportioni
nradialdirections，andthes
elooklikev
ein
s on blade when they
growt
hicker.
Growthof the thallu
sis by meanso
fa
per
ipher
alser
ie
so
fi
n
it
ial
s. The blade iscomposed ofalayerof epiderms and a
medulla of two or more layer
so
fc
el
ls.
Epidermalc
ell
sar
ec
ubictocyl
indr
ica
landcontainmanysubspher
icalchromatophores.
On themargino
fthebladet
hemedullary，butcellsarelar
ge and elongated(Fig.1)
becomeshor
tertowardthec
entr
a
lpor
t
ion
t theoft
he blade (Fig.2). Therefore，acentralportionof the blade themedullarycellsar
ec
ubo
idali
ns
hape. Inatransv
ersesectionof a frond i
twillofte
n be seen，severalepidermalc
ellscor‑thatinwidthrespond toa singl
emedullarycel
lon themargino
ftheblade(Fig.1). Butprogres‑sin
g toward the median por
t
iono
f the
rtwoepidermalc
ell
scor
‑bl
ade，onlyoneo
respond to each medullary celli
n width(Fig.2). Themarginso
fyoungbladesaresmooth，but as they growo
lder，some ofthemarginali
nitialcell
sdiv
idepericli
nallytoformfilaments(Fig.3). Thesefilamentsar
e simple，uniser
iate，andwith chromato‑phores，buti
nr
ar
ec
ase
stheymaybranch

166.‑M.and CI‑
IOU，H.
‑N.
CHlANG，Yspa
r
ingl
y.
Of particular significancewas th巴 forma‑tion ofg巴I11l11ae (Fig. 3)along t
h巴 margi
nof t
he t
hallus. The g巴I11l11ae origi
nate巴ith巴rfr
OI11 th巴 apicalor cel
ls inth巴 me‑

Figs. 1‑4.

ich aredian porti
on of the filal11ents whproducec
lfr
Ol11 th巴 巴 clgeo
ft
he blade，espe‑
h巴 olderorc
lal11ageclcially from t
hos巴 on t
portions. The fi
rstc
livi
si
on of theg巴I11l11a巴川 it
ial is t
ransvers巴Gel11mae are fan‑

ZOJ/a1'iαstψilata TANAKA et NOZAWA

1. A tr
ansv
ersesect
iont
hrolgh themarginalp
arto[thethalllls x300r
ansv
er
sesection thrOl
lgh t
he median part of t
he t
halll
ls x2
00.
2. At
3. A port
ion oft
het
halll
ls，showi
ng 日laments anclvar
iOlS stages ofgem maegrowing Oltfrom t
he margi
noft
he lhalllls x60. 4. A ma‑tlregemmaeseparatecl fromathall
usx30Zonar.
i
包 st
i
pitat
ainTaiwan

shapedwithlong，uniseriateormultiseriatestalks(Fig.3). I
tseemsthatfurtherdevel‑
opment of blade，stalk and basa
lpor
t
ion
may cause detachment of the maturegemmae from the mother plant(Fig.4).
KUMAGAE (1977) reported thatthe samekindofgemmaeformationwasobservedi
ntwoothers
peciesofDictyotaceae，Zonaria
diesingiana]. AGARDH and Pachydictyolll.MES) OKAMURA and undercoriaceum (HOcultura
lexperimentthegemmaegrewi
ntoadultthalli.
No reproductiv
e organs were observedin anyofourspecimens. Therefore，fromthe specimens at hand and thereportsof
TANAKA andNOZAWA(1962¥，Ho(1969)andt seems thattheformationTSUDA(1972)，if ever，of reproductiv
e organs rarely， ioccurs. Gemmae formation appears tocommon and may be the only methodo
fpropagation innature.

1
6
7

Acknowledgement
W e express our sincere thanks toDr.
YING・MINGCHEN，Miss].E.LEWISandMr.
C.S. CHENfortheir kindness in sending
us speClmens.
ReferencesHo，P.H.1969. M
arine algaeof South Viet‑ieuXuat‑
BanPress，Nam. Trung‑TamHoc‑LSaigon.(lnVietnamese)
KUMAGAE，N.1
976. M
orphogenesis inD
ictyo・otalesX
I. Tetrasporeger
minationofSか，'P‑
podiulIl :zonaleandPaduzac
rassa.Bul.
l]ap.
Soc.Phycol.2
4:92‑
97.
TANAKA，T.andNOZAWA，
K.1962. SomenotesOllariaintheon thegenera Padina and Zsouthwester
nislandsof]
apan. Mem. Fac.
1:1
7
9‑
187.
Fish.KagoshimaUniv.1
TSUDA，R.T.1
972. M
arine benthicalgaeof.P
haeophyta.Micronesi阻 止 8
7‑
115.
Guam1

江永棉・厨宏鹿= 台湾産のエツキシマオオギについて
エツキ・ンマオオギ Zonari
astip必ataTANAKAetNOZAWAが台湾南部の地点から採集されたラこの標本には生殖細胞の形成はみられなかった 3 葉体の縁辺から生ずるー列細胞糸に無性芽が生じているのが観察された、天然、ではこの無性芽によって繁殖していると考えられる。(中華民国台北市 国立台湾大学海洋研究所)