瀬戸内水研報（Bull．Fish．Environ．InlandSea），No．1：163−165（1999）

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1999年2月26日受理（Accepted on February26，1999）
瀬戸内海区水産研究所業績A第8号（Con匝bution No。A8ffomNational

内田卓志・松山幸彦・神山孝史：瀬戸内海区水産研究所
T．Kamiyama：NationalJapan）

ResearchInstituteofFisheries

Research Institute ofFisheries andEnvimment ofInland Sea）
〒739−0452 広島県佐伯郡大野町丸石2−17−5（T・Uchida・Y・Matsuyama・andandEnvironmentofInlandSea，2−17−5Mamishi，Ohno，Saeki，Hiroshima739−0452，

CellFusion

inD

AtlasofUnicellularandFlagellatedTokyo，p，6−7。（intheLi￡eIn：T．Hori（ed．）。

History

Algae．

ofAn

Algae，Volume3．

rates
spp・onJ。H。Ryther，1962。Studies

onsexualmarine

genus

which

canactno函y3∫3−abothasaplanktonic

preyan（ldino且agellateapredator

Inoue，H．，Y．Fukuyo，an（1Y。Nimura，1993、Feeding
dinoflagellate，0ηphy8∫s

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β麗JJ・Japanese）

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lifle

cycle？

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s．In

for

T．J．Smayda

B．V．，143−146．

ans律

α言扉nl

photosyntheticonloricatedin

aspecies

Bloomsinthean（1Y，Shimidzu），Elsevier

Uchida，T．，Y．Matsuyama，and
bysexuality

ToxiσPhytoplankton（ed．bytionofSeaScienceT。Kamiyama，1997。Preda−（1inonagellateciliates．

1．PJαη丸置onG）7704

π彪溺Rεs．，19，603−608．
Yasumoto，T。，Y。Oshima，W。Sugaw肛a，Y、Fukuyo，H。Oguri，T．Igarashi，and N．Fujita，1980． 1〔1entification ofnophy53／bπ髭astheshellfishDpoisoning，

β麗Zムゆn。Soo．Sc

causativeorganism．Fof

dianrhetic

sh。，46，1405−1411．

α，ρ。

松山a

Phy60Z。，28，399−406、dinoflage1一培養中に観察された」胱nophys

下痢性貝毒の原因種であるD

dinoflagellates

Publishers

behavior

Jacobson，D．M．and R。A．Anderson，1994．The discovery of
mixotrophy in photosynthetic species of P加01，hy3 s（Dinophyceae）：1ightti（leDどno1アhy3

ciliate．ハ4砿EcoZ．P708．Sα，，69，201−204．
ofredheteronfophic

McLachlan，J，L，1993，Evidence

8，229−239．
DtheMacKenzie，L，1992。Does

planktonic〔1iatoms。1， CyoJo言ε伽nαnαHustedt andDε診on吻oo漉押αoω（Cleve）Gran。Cαn訊履070わ∫oZ。，
Hansen，P．J．，1991。

of

α，33，97−110。

M．1。Latz，1994．Growth106，173−185．

Uchi〔iaroukakuho，Japanese）

Guillald，R．R．L．and

Phy60108

Jeong，H，J。and

nophysぢ3／bπ蕗。

Illustrated

165s1ates．

Refere皿ces
Fukuyo，Y、，1993，Z万nopんys

sヵ7痂の細胞間融合について

内田卓志

幸彦

神山孝史

nophys5ヵ漉∫を三重県五ヵ所湾から分離・培養したところ，栄養細胞接種後10日目から楼小性の細胞が観察され始めた。楼小性の細胞は形態的に栄養細胞と同一の細胞と結合し，やがて飲み込まれるようにこの細胞と合体した。合体を完了した個体は栄養細胞とほぼ同じ形態を保ち，単離・培養後も約2日間は活発に遊泳を続けた。このように本報告ではD．ノb7薦の細胞間融合についてその過程を連続観察に基づいて述べるるとともに，有性生殖との関連について考察した。