BIOLOGY OF CLONORCHIS

SINENSIS

bl'

YOSHITAKA KOMIYA & NORl]l SUZUKI

PREFACE

Since the dicovery of Clono7chis sinensis by MCCONNEL (1875)， the biological，

pathological and clinical studies on C. sinensis have been carried out by many

workers of al1 the countries of the world

The initial description about C. sinensis in ]apan was made by ISIIIZAKA

(1878). He detected the worrn from a farmer in Okayama Prefecture (The

formal detection of C. sine耐 iswas described by BAELZ). Thereafter the study

on the worm in ]apan showed a marked advance. In 1910 K06AYASHI discovered

that cyprinoid 白shesserved as the Intermediate hosts of C1Qnorchis infection

In 1918 MUTO found the first intermediate host to be an aquatic operculate

snail. These discoveries have not only made clear the life cycle， infection

route， geographical distribution and preventive measure of the parasite， but

also contributed to the far-reaching development in the biological study of

C. sinensis

Thus， many studies about C. sinemis by wokers of ]apan occupy a

distinguished position in the parasitological society of the wor!d

Here these studies in the biological field with the life histoγy ，γe to deal with as the central theme

J. SCIENTIFIC NAME

The scientific name of this species was fixed upon C/onorchis sine肘"

(COBBOLO， 1875) LOOSE， 1907 through many troubles， and the discovery and

study of the worm in )apan played an important role in the determination of

the scientific name

The worm was obtained initially by MCCONNEL (1875) at autopsy of a

Chinese carpenter rεsiding in Calcutta

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MCCONNBL sent it to COsBOLD to ask fOf its identi行cation，whereupon

COBsOLD (1875) gave it the name of " Disloma sinensis"

Later on BAELZ (1883)， having di配 overed the ¥Vorm accidentaJly On an

autopsy of a patient suffering (rom pulmonal tuberculosis in the Tokyo Uni

versity Hospital， distinguished two species: viz. Disloma heρ'1lis innocltum

and Dislomαhepalis endemicum siι'e terniciosum. He thought that D. h. innOCUlO1f，

a larger form， had no pathogenicity and the other， a smaller form， to be of

pathological significance. This differentiation of two species by BAE!.Z met with

many oppositions. I[JIMA (1886) recognized that both剖 eidentical， and referred

the worm as Distomum endemicum BAELZ. LEUCKART (1886) and BLANCHARD

(1895) amalgamated BAELTZ'S two species into one， especially the latter creat

ing the genus Otisthorchis to include this species and referring it as OtislllOrchis

sinensis (COBsOLO)

Meanwhile， LooSE (1907) who took the distinct tWQ species over again，

suggested tnat BAELZ'S D. h. innocuum should be another species， though

BAELTZ'S D. h. endemicum and MCCONNEL'S showed the same species. And he

created the genus Clonorchis and included them in it

1. Clonorchis sinellsis (COBBOLD， 1875) LOOSE， 1907

2. Clonorcllis叩 demicus(BAELZ， 1883) L∞S芭， 1907

Later， KOBAYASHl (1912a)， having made a study on the development of lhe

worm in various definitive hosts， stated that the size of the worm depends

upon the size of the host as we¥l as the number of parasite in one host， and

that other morphological differences including the shape of eggs between the

two species of LOOSE was not distinct

Thus he came to the conclusion that only one species of Clol1orchis sinensis

(COBBOLD， 1875) LOOSE， 1907 should be γecognized. This opinion is now generally

approved

11. ADULT ANATOMY

!，he structure of Clonorchis sinc1ISis has been carefully described by

KOBAYASHI (1912a， 1922)

A. Externa I Form

1. Shape， size and general apr加earance

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Accotding lo KOBAYASHI (1912a， 1922)， C. sinensis is markedly flat and the

posterior two thirds have an equa! breadth and anterior1y the body slightly

tapers. The size o( the worm varies according to its age， species of the

h051， number of the parasite in onc host and lhe type of fixation. it5

maximum and minimum length measuring 4 20mm. Generally speaking the

size of C. sinc同時 rangesfrom 8-15 mm in iength by 1.5-4 mm in width. The

living specin、enis transparent and slightly pink or brownish il1 color and has

yellowish or brownish pigment in the body. The size and color of the pigment

granulcs differ in different individuals and even in the same individual

KOBAYASIII assumed such pigment i5 due to the shell material from the vitellaria

The oral sucker lies at the anterior end and the ventral one is situated at

the level of one third or one fourth of the body length from the anterior end

The oral sucker (0.4-O.5mm) is usually a little larger than the ventral one (0.3

0.45 mm) in diameter

2. Cuticula and subcuticular tissue

The cuticula of the full grown specimen is relatively thin and has no

structure armed with no spines. The subcutaneous muscles are cons回 edof

transversal， longitudinal and diagonal layεrs. Under these muscles a layer of

subcutaneous cells is found They have a spindlc shape in younger

individuals. In full grown specimens， however， they are piliformed or star

shaped

The structure of the parenchym is of a reticular type with relatively fine

mesh and among the mesh cells of the vesicular type are found scaltered

Gianl cells of markedly large size are found in the muscles of uterus，

seminal vesicle， subcutaneous muscle， sucker and pharynx. They connect with

vanous organs 、，vithprocess

B. TnterJHlI Organ

1. Digestiv巴 organ

It initiates at the oral sucker and consists of pharynx， esophagus and

bifurcated川 testine. The intestinal ceca terminates a1 the posterior end of the

body. The pharynx is spherical with its inner surface cove問 dby cuticula. Its

wall co岡崎tsof well developed muscles. The inner wall of esophagus is covered

with a relatively thick cuticula and well develoI施 dtransversal and longitudinal

mu配 Ies. The intestine has epitherial celJs川 thewall and its exterior is

equippcd with transversal and longitudinal muscles， which are le田 developed

as compared w此hthe esophagus ones

2. Excretory system

The excretory pore opens at the posterior end. An excretory bladder is

1 shaped situating at the posterior part of the body. The main excretory canal

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starts frorn both upper corners of the triangle of the excretory bladder

and runs upwards laterally across the intestinal caeca to the mid-body level，

wherεit divides into the anterior and posterior collecting tubes (KOBAYASHI，

1912a， 1922)

3. Nervous system

OZAKI (1960) observed the nervous system of C. sinensis by staining the

nervous celJ and fiber with mercury. He in白ltratedmodified Gilson's so¥ution

into the伺ukeby the aid of citric acid and deoxidized it by means of the

sun ray to precipitate the mercury in the nervous cell and fiber. According to

his observation the nervous system， as such is the case in trematodes in

general， consists of supra-oesophageal nerve commissure and three pairs of

longitudinal nerves (ventral， dorsal and lateral) running from both ends of the

former anteriorly as well as posteriorly. As compa同 dwith the well-developed

ventrallongitudinal nerve， the other longitudinal nerves are too poorly developed

to percelve

The huge nerve cells are arranged laterally sporadicaJly. The axial

filaments originating from them gather to forrn the longitudinal nerve. The

ring commissure connecting the longitudinal nerves was of reticulate structure

OZAKI (1960) considered that the undetermined running direction of the

nervous tissue in the reticular structure indicates the undifferentiated primitive

structure

4. Reproductive organs

The common genital atriurn opens median ventrally directly at the front

of the acetabulum and both malεand female organs unite directly before the

common openmg

a. Male genital organ

The male genital organ consists of two testes， two vasa eferentia， a

seminal vesic1e and an ejaculatory duct. The testes are dendritic， lying tandem

。nmedian line. The an担 riortestis has four branches and the posterior five

ones. These main branches a問 divided into irregulal' branchlets， but the

aspect how to branch is indefinite

The vas eferens arises from the center of the dorsal side of each testis

The two ducts from each testis run forwards for some distance and unite

together about at the middle part of the uterus winding， after forming itself

as a thick tube， opens directly into the seminal vesic1e

The seminal vesic1e runs sinuously anteriorly along the dorsal side of the

anterior portion of the uterus， turns ventral1y along the right margin of the

acetabulum， goes on 出m目指hingits diameter and forms itself as the ejaculatory

duct， which opens at the region of the anterior margin of the acetabulum

Fig. 1. Nervous system of ClonorcJ/Is $i l/e l/ú~

(OZAK1， 19略0)

1. Longitudinal nerve and nerve cell

Z. Nervous system of anterior part 3. Ne汀voussystem of posterior part

A Ventral sucker

A D N: Anterior dorsal longitudinal nerve

A L N: Anterior lateral longitudinal nerve A V N Anterior ventral longitudinal nerve

C N: Ring commi悩""o K Dorsal subcuticular surface nerve net

E: Esophagus

Inlestine

N C: Nervous cell

o S Oral sucホ"P D N Posterior dorsal longitudinal nerve

P H: Pharynx

P L N: Posterior lateral Iongitudinal nerve

P V N: Posterior ventral longitudinal ne円 e

S E N Supra.oesophageal nerve commissure

V K: Ventral subcuticular surface nerve net

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558

along with the female genital opening

b. Female genital organ

The female genital organ is composed of one ovary， fairly、velldeveloped

vitelline glands， Laurer's canal， big seminal receptacle， ootype and uterus

(Fig. 2)

Fig. 2. Various reproductive organs which take place the formation of the egg-shell (UJlIE， 1936)

m d Meh1is' gland

， ， ∞'YI" o v: ovary b y canal of KOsAYASHI'S egg-cell sucking

'P凹 ratuso d: oviduct d yolk sac

d c yolk duct r s seminal receptacle 1 C LAURIlR'S canal U t uterus

1. Vitel]ine gland and vitelline

cells

Both vitelline glands lie

exteriof to the intestinal ceca

They range from the level of

the anterior margin of the

acetabulum to the level of ovary，

and consist of many small glands

(KOBAYASHI， 1922). With a

fresh specimen they a問 slight

yellow i11 color forming an ap

pearance of a congromerate of

numerous grape-like bunches

Wはh a fixed specimen they

are dyed distinctly with various

stains， whereupon they can

be distinguished from the other

organs as an ovoid congro.

merates. The gland is a cavity

surrounded by a thin membrane

buried deeply in the body cells

and contains 8 to 20 vitelline cells

of diverse developmental stages

(UJI1E， 1936)

In山 ally the vitelline cells

are spheroid in shape attached

one another， holding in them the

evenly compact protoplasm

In the co山田 oftheir develop-

menl the light yellow minute granules are found di抽出utedevenly in the

protoplasm. Later the cell membrane has developed and the granules become

gradually bigger in size (UJ!1E， 1936)

No borders can be observed between the vitelline gland and vitelline duct

but the former gradually makes itself as a fine tube. The tubes gather into

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two longitudinal vitelline ducts arranged on both sides of worm. They consist

of anterior and posterior branches which unite to become a transversal vitelline

duct at the region of the posterior end of the vitelline glands. The right and

left transversal vitelline ducts united in one， which swells up to make it田 lfas

a so called yolk sac. The yolk sac， with the narrow duct， bending like a bow，

opens to the oviduct at the position where it passes into the ootype (K06AYASHI，

1922; UJIIE，1936)

According to UJIIE， (1936)， it has been ascertained that both the movements

of the yolk sac itself and the peristaltic movement of the oviduct transport

together the vitelline cells one by one from the yolk sac to the ootype

2. Ovary and egg-cel1

The ovary lies on the median line- anterior to the anterior testis， and

conSIS臼 ofthe mass of egg-cells of various growth stages and is surrounded

by a thin membrane. It is composed of three lobes. The egg-cel!s in the

centl'al dorsal part of the central lobe are found more developed. The oviduct

initiates from the blind duct near the dorso.central part of the central lobe

and reaches the ootype (UJIIE， 1936)

A ductus is observed on the surface of the ovarian part connecting the

oviduct and ovary. It is a called “spermatheca" of Looss (1894)， or "suction

apparatus" of KOsA Y ASHI (1915). The wall of this apparatus expands and

contracts periodically to suck the matured egg-cells from the ovary and

transports them to the oviduct

The content of the oviduct is spermatozoa， which comes from the uterus

and is to be transfered to the seminal receptacJe

3. Mehlis' gland

The Mehlis' gland lies anterIor to the ovary and the gland is distributed

in the semトcirculararea dextral to the ovary with the radius about O.3mm

at the central lobe of the ovary. Around this area a large numher of glandular

cells are scattered. Their fine ducts gather at the central part and open into

the ootype found there (UJIIE， 1936)

4. Ootype

The oviduct connects itself with the ootype after uniting with the yolk duct

The ootype is a spindle-shaped cavity surrounded by Mehlis' gland. It measures

O.033mm. in length by O.023mm. in width and is connected with the uterus

(UJIIE， 1936).

5. Laurer's canal and seminal receptacJe

The Laurer's canal 凶 relativelylong and connects wIth the beginning of

the oviduct. The seminal receptacle is ovoid or piliformed (O.6.1.2xO.2-0.6mm.)

The lumen is usual!y filled with spermatozoa

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After having a connection with the seminal receptacJe， the Laurer's canal

runs somewhat towards the abdorr】inalside a100& Its Ieft side of the latter and，

after turning inwardly backwards， opens at the anterior margin of the anterior

testis (KOsA Y ASHI， 1912a， 1922)

6. Uterus

The uterus is a curved 100g tube， occupying the area surrounded by the

tWQ intestinal caeca， the Qvary and the acetabulum， being filled with eggs

C. Histochemistry of the Fine Structure

00 the distributioll of lipid and its nature 00 C. sine出 is，MURAMATSU (1927)

reported that the sedimentation of the fat in every organ of the f1uke from

men was higher as compared with that from cats and dogs. The cholesterol

ester was seen in the parencymal ceJ1s and intestine of the fluke from men

but in small amounts in the fluke from cats， and none from dogs. In the

excretory organs the fat was found only in human parasitic cases. In the

parenchymal cells γelatively large amount of neutraI fat and lipoid was

found

SAWAOA (1926) examined the worm three years and three months after

the infection and found that in older worm配 niledegenerations were recognized

with decreased glycogen amount， whereas fat was found increased

Recently， TAKAGI (1962) examined the distribution of the fat， polysaccharide，

nucleic acid and the phosphatase in C. sinensis. The results showed that the fat

(neutral fat) was present in oesophagl1s， epithelial cells of intestine， and

parencymal cells around testis， oval"y and seminal receptacle most abundantly，

that glycogen in parencymal cells and spermatozoa， whereas RNA was present

in muscle tissues and female germ cells and DNA in male and female cells in

large amounts. Alkaline and acid phosphatase were found orominently in intestine

.and vitelline glal1d

III. THE EGG-MIRACIDIUM STAGE

A. Pormation of Egg.Shell

The detai!ed study on the formation of egg-shell by UJlie (1936) is available

According to him， one matured egg cell appears in the central part of the

surface of the middle lobe of the ovary， and arrives at the in山 alportion of the

-ootype through the oviduct 、Nhenthe egg cell passes throl1gh the

the yolk duct to enter the ootype， the central part of the yolk sac almost

suddenly contracts so as to form an arc-shaped narrow part. And subsequently

its lower part autornatically makes rhythmical movements which makes the

vItelline cells enter into the yolk duct one by one. The duct take渇 aperistaltic

movement so as to transport the vItelline cells to the ootype following one by

one after the egg cell

The formation of egg-shell takes place in the ootype. When the vItelline

cells increased by 5 to 7 in number， the yolk sac suspends its movement

for a time. In the mean time these cells attach themselves to the egg cell

lying in the initial portion of the spindle-shaped ootype and fill up the ootype

At this stage the terminal part of the oviduct contracts and its opening to the

ootype is closed. Then the ootype dillates， and makes space between these

cells and the wall of the cavity

COllsequently the shell forming

granules are released from vitelline

cells and gather around them to form

the egg-shell. When the ootype 也icontracts， a part of these granules

constituting the wall extends back-

ward along the constricted wall of

the oviduct as the fine tube， which

is reduced to become the posterior

spinal process of the egg. i. I (I01

When the ootype again dilates，ト-

a small space occurs at the anterior

portion of the egg uncovered with

the granules. Consequently the

granules adhere to its surface

secondarily and form the operculum

Then， the egg is transfered to the ι

If 11) uterus (Fig. 3). L:...:....:....

UJIIE(1936) states that the Mehlis'

gland plays an important role in the

formation of the egg shell firstly by means of its characteristic automatic

contractive and dilative movements and secondly by its secretioll

50'

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AMVL

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戸川比 命

A

企同wvト

Le

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Fig. 3. Formatio、。fegg-shell in the ootype (UjllE. 1936)

s. Ferti1izntion

NAKAYAMA (1912) asserted that the fertilizatioll was sometimes completed

in the oviduct and that the egg cell had， after being enclosed in the egg-shell，

already been fertilized by the spermatozoa and the egg cell kept on its original

562

state stil! after the ferti!ization. The egg-cell was enclosed in the egg-shel1

after completing the fertilization and transported to the uterus as the complete

egg

UJlIE (1936) also considered that the egg cel1 had met the spermatozoa from

the moment of its appearance at the beginning of the oviduct up to the time

when the operculum、.vasformed in the ootype， since the active spermatozoa

were found numerously in the oviduct， especially in its beginning

c. Dcvelopment of Egg

The initial study on the embryonic development was made by SA!TO (1898)，

which was followed by the detailed observation of NAKAYAMA (1910)， and later

by KOBAYASH! (1922). To summarize their results， the egg， after forming the

egg-sheJl at the beginning of the uterus， is usually composed of an egg cell and

5 vite11ine cells. The egg cel1， in which already one spermatozoon entered，

lies anteriorly in the egg-shell

The vite11ine ceUs attach themselves to one another after releasing the shel1

forming granules and their outline becomes indistinct. The germ cell has six

chromosomes. By the maturation of the geγm cel1 the two polar bodies are

released out and the chromosome becomes 3 in number. After the fertilization

its chromosome amount to 6 ill number by adding another 3 from spermatozoon

The fertilized egg-cel1 starts the cell division， which is equal and holoplastic

cleavage. Along with further divisions， a cel1 is separated and removes to the

portion near the posterior end of the egg， divides， and gradually forms a

vite11ine membrane. Then， the two cells detach from the embryo posteriorly

These ceJ1s divide graduaUy臼 kingthe appearance of foam， and adhere to the

vitelline membrane partially. These cells and the shell membrane perform the

function to keep the embryo in the fixed position

Then the ectoderm become differentiated from the blastula and the

miracidium is developed. It covers with several rows of ciliated fiat plates， except

the area where the cells of foam appearance attach the embryo. In the anterior

part of the embryo a primitive gut is found conical in forrn. ln the postrior

half of the body a group of cel1s which corresponds with the embryos of the

next generation is recognized

D. Shape and Size of the Egg

1. Malure egg

The morphology of the egg of C. sinensis has been observed by tnany

workers (IUIMA， 1888; LEUCKART， 1889; OOTANI， 1892; OSAFUNE， 1898a，b; SA!TO，

1898; ISHII， 1929a). It measures 0.026.0. 030x O. 015.0. 017 mm.， ovoid in form，

narrowing a ¥ittle posterior to the portion of the operculum. The op町 culum

takes the shape of a watch-glass with the prorninent shoulder-¥ike rirn and is

563

found on the narrow anterior end of the shell. The shell is about 0.005-0.008 mm

thick. According to FAUST et al. (1927) and HASEGAWA (1929)， the surface of

the shell shows etchings of an arabesque polygonal pattern. HASEGAWA states

that the pattern is based on ¥ines projecting to the surface of the shell. YUMOTO

(1936a) reported that the shell was composed of two layers. The inner layer

was yellowish brown and a ¥ittle thick as compared with the outer. Its thickne日

was uniform throughout. The outer one was light greenish yellow in color and

thin. I-Ie stated that the outer layer was hardly distinguished from the inner

one by the light reflexion

2. Abnormal egg

KITAMURA (1916) found the egg without the operculum and regarded it as

the unfertilized egg. FAUST el al. (1927) made a brief description on the egg

without the operculum under the name of the imperfect egg， and stated that

its contents consisted of an egg either lacking yolk cell and granules or egg cell

ls削 I(1929a) reported that he could differentiate 4 kinds of abnormai eggs in

stool， and that these eggs were produced by the worm of which vitality has

weakened

YUMOTO (1936b)， who made the ob措 rvationon abnormal eggs， divided them

into the two groups， namely “abnormal" egg and "incomplete" one. Both

eggs have the shell of the same structure as normal one. The former， however，

has no operculum， though the etching of the arabesque polygonal pattern can

be found on the surface. Its content is degenerated and a drop-like substance is

recognized in it. The latter holds no miracidium， though it is possessed of the

operculum. He states that the "abnormal" egg is always produced throughout

the worm's life， but the “incomplete" one is produced l1umerously by the

initial egg laying period of the young as well as by the senile one

UjlJE (1936) considered that abnormal egg was produced when the worm

either was young or very old， or when it is affecred by an abrupt change in the

surrounding and an e仔ectof anthelminthics etc. He deduced its mechanism

as follows: 1) A temporary suspensIon of the egg cell delivery alone into

the ootype due to immaturity and senility may result in the formation of Ilon

0"，，'印lated，no egg-cell eggs. 2) When one or t¥¥lO vitelline cells arrive at the

ootype in advance， non-operculated eggs containing an egg cell may be formed，

and 3) operculated or non-operculated eggs with multi-egg cells may be formed，

when more than two egg cells arrive in the ootyp巴

E. Egg-production

Egg-production by C. sinensis varies with the kind of t

564

noticed that the egg-Iaying capacity of C. sinensis in those animals remained

the same during six months after the infection. Later KAWAI (1937) ob田 rved

the egg-!aying capacity of C. sinensis in experimentally infected dogs during six

months and gained the same result of FAUST el al. above-mentioned. Prior to

KAWAI， YUMOTO (l934) observed 00 the egg-production of C. sinensis in

experimentally infected dogs by using the Wakejima's egg counting method

(WAKEj[MA， 1932)， and reported that the number of eggs per day per warm was

apporoximate¥y 2，凹0

Recently WYKOFF (l959) ohsεrved its egg-production in 16 rabbits for a period

up to 55 weeks after the infection， the result of which showed that the eggs

increased steadily up to the 17th week and the cyclic variation of every 10 weeks

was noticed. The mean number of eggs per day per worm was ca. 4.000 and

that per gram of feces per worn、wasca. 100. SAITO et al. (1961) noticed also

the cyclic variation. The mean number of eggs per gram of feces per worm

in rabbits remained constant except for ca配 sin which the number of worms

was few in number. According to them， when the numbers of the worms

recovered were 19， 77 and 444， the mean number of eggs per gram of feces per

worm were 260， 216， and 231 and those of dry feces were 502， 353， and 310

respectively. They stated that a rough estimation of worm number in rabbits

could be made on the basis of the fecal counts

IV. THE FIRST INTERMEDIATE HOST OF

C. SINENSIS AND ITS DEVELOPMENT IN HOST

A. Tlte Species of the First Intermediate Uost

It was MUTO (1918) who discovered the snail intermediate host of C. sinensis

In the cour詑 ofcollecting hundreds of fresh water snails of various kinds

in Lake Biwa， he found the two species of cercariae in an unknown snail and

after infecting experimental1y Pse.udorasbora parva with tho目 cercariaehe was

able to find the Clonorchis metacercariae in the ftesh of this fish. This snail

obtained from Lake Biwa by MUTO (1918) was identified as BilJzynia sirialula var

Jaρonica (PILSBRY) by HIRASE. This snail was sent to PILSBRY previously by

HIRASE for identification and the latter recognized il as new and named it as

such (P!LSBRY， 1907)

565

According to PILBRY， its shell is light-amber Or horn-colored and glossy，

and resembled B. slrialllla from China. But it differed from the latter in the

following points: in sculpture， in the spiral striation being much stronger， in

the point that in 3 or 4 large and irregular thick rib on the periphery. It

measured 10 mm. in length， 6.5 mm. in diameter and 5 mm. in the longest axis

of aperture. PILSsRY considered that the snail from Japan was a variety of

that from China

In 1924 ANNANDALE et al. created the sl1bgenus Parafossa叩 l附 to inc¥ude

this species. But WALKER (1924) entitled it to the generic rank. As to whether

the snail from ]apan is identical with that from China or not， several authors

(KUROOA， 1913; SHlBA， 1934; OKABE， 1938; KOsA YASiII， 1950b) discus四 d. ABsOTT

(1951) suggested that the snail from )apan and that from China should be

incorporated into one species of Parafossarufus manchouricus BOURGUlGANT

SUGIHARA (I954b) carried out a morphologica¥ study on 柏崎町ai¥from various

areas in )apan， and concluded that the two kinds of snai1s above mentioned，

shou¥d be distinguished neither by the shell scu¥pture， nor by operculum form，

nor by radula formula， revealing that both snai1s should be called as

Pαrafossarulus manchouricus BOURGUIGANT

B. J~cology oC the Snail lnternもedillteHost

1. Development

SUGIHARA (1954a) observed that the oviposition took place from the middle

of May to thc middle of )une (water temperature: 20・ι24・C)under ¥aboratory

conditions. The eggs in one egg mass was apporoximately 20 to 22 in number

The egg hatched about 20 days after oviposition. Young snails developed

quickly in size until the middle of September， though the growth rate was

diminished transiently in midsummer. After November印制lscraw¥ed into the

mud and stopped its activity ur凶 1the end of March. One to two months later

a young snail developed into a slender one in shape from its former short and

thick size and took the same size of an adult about one year after hatching

2. Habitats of the snai1

JITSUKAWA (1953) reported that at the downstream area of the River Tone

the habitat of the snail was the sut"Iace of mud in water bed with the water

grass， where the water was abundant with sluggish Row. NISHIMOTO (1958)

observed in Tokushima Prefecture that the snail habilat was the Iow swampy

area belonging to the alluvial Iayer with sIuggish fresh water， with thc watcr

beds plenty with mud and organic materials， and whcre in summer watcr

grasses thrirved and evcn in wintel. no dry up of watcr obse

566

、'1atertemperature， hydrogen ion concentration， chlorine content， content of

organic materials， etc

a) Watcr temperature

00 the effect of temperalure 00 the activity of the vector snail the studies

by NAGANO (1928)， KUYAMA (l938)， llTsuKAwA (1953) and INATOMJ (1953a) are

available

According to KUYAMA (l938)， the snail crawled into mud at the tcmperature

of 12・C，and as temperature became higher snails pre由 ntcdthemselv曲 on

mud (12. B・C: March， 28). And sl1ails， having crawled 00 mud (12.8・ι18.9.C; Mrach， 23-April， 27)， adhered to the water grass or piles (18.9・C;April， 27)

when the budding of water-grass was observed. JITSUKAWA (1953) I巴portedthat

the snail began to crawl 00 mud when the watcr temperature rose to 10・CWith the rise of water temperature it adhered to the rear of grass leaves for

egg-Iaying

b) Chlorine

NAGANO (1928) statεd that the snail died in 30 %日awater as well as in 0.3

% saline water (in 100 cc， chlorine content 182 O1g.) within 24 hours

NIS旧 MOTO(1958) surveyed the content of chlorine in several water areas in

Tokushima Prefecture，副dreported that in the habitat even at the time of ebb

tide in November and December a fairly high value of chlorine content (63-351

mg.!l， in average 201 mg./l was obsεrved， This value was， however， markedly

low as compared with that (1， 825-3，495 mg.ll) of areas in the vicinity of the

river mouth， where no snails were found. SATO el al. (1959) measured the

amount of chlorine in waler of the habitat in several areas in Ishikawa

Prefecture， and noted that the maximum concentration of chlorine tolerable

for snails was 200 mgJl. INATOMI (1953a)， however， was of opinion that the

temporary flowing water containing chlorine as described above had no effect

on snails， and that the amount of lO mg.ll of chlorine in water would favour

the snail

c) Hydrogen ion concentratiol1

No work was available as to hydrogen ion concentration conditioning the

snail survival. INATOMI (1田3a)observed， however， that the pH range 5.0-7.0

had no inftuence on the development of snails

d) Organic matter

INATOMI (1953a) surveyed the amount of organic matter by measuting

consumed quantities of potassium permanganate in water in Okayama Prefecture，

and reported that the snai1 showed a more favorable deve10pment in water with

dch amount of organic matlet. NISHlMOTO (1958) a1so examined the organic

mattet on the habitat of snails in Tokushima Prefecture by the same method

567

The results show巴dthat in the areas where snails were abound the consumed

Quantity of pota盟国mpermanganate in watcr was 82 to 269 mg.ll， 175.5 mg.11 in

average， while in rivers and ditches where it was 18 to剖 mgμ. 29 mg!l in

average，回ailswere found smaller in size and underdevelopcd

NAGAMQTO (1959)， in the snail habitat in the downstream area of the River

Onga， observed that in the hahitats where snails were found ahundantly the

scwage watcr with the rest of foodstuff etc. Rowed from residcnccs叫 arwould

act favorably on snai1s. General1y speaking， a cerlain amounts of organic

mattcr would promote the thriving of watcr plants， which，同 turn， leads to

favor of the propagation of snails (NAGAMOTO， 1959)

e) Olhers

A certain amount of NH" NOJ and hardness had no harmful effects on the

snails (INATOMI， 19也3.)

4. Fauna and但or.

In the rivers and ditches inhabited by vector snails， SHIBANO (1933) found

。thersix species of snails; Crislariaρli回 tasta/io血， C(ρangopaludina 11Ialleala，

Corbicula leana， S初出ulcosPi目 白 河5On;，Ly11lnaea japonica and Bu/i11l叫 11Iise//us

INATOMI (1953a)， JITSUKAWA (1953)， NAGAMOTO (1959) and IKUYAMA (1960) found

(he same species of snails in the habitat of Parafossa四 lussnails

Water plants， in the as耳目ionby NAGANO (1928)， play an important role in

the breeding and subsistence of snails

ln the snail habitat in the middle strcam area of the River Tone， the

following plants were reported by KOMIYA et al. (1950): Val/i訓 eTW噌iralis，

Myrioplzyl/u11l vertici/latum， Najas minor and Hydri//a verlicilata. Thcse watcr

plants， growing O. 3-l. 0 m. under the water surface， were adhcrcd by vector

snails

NISHIMOTO (1958) a1so rεported that snails were found attached to the root

of water p1ants such as Vallisne川柳町lis，Chara coronata， Myriophyllum

四 rticil/atll11/， A秒rioph.メIU11/spicatum， EichllOrnia crassl~抑s and Nuphar jaρonJcum

elc. which were to bud on the water bed towards the end of April. Snails

were also found adhercd on the surface of water plants like却irode如何lyrhi掴

and Trapa nalans， and reeds growing in water on lhe margin of the river

NAGAMOTO (1959) and IKUYAMA (1960) also gained the same results as those of

KOMIYA el al. and NISIIIMOTO

C. Development of C. sinensis in the Snail H08t

1. Miracidium

The morphology of the miracidium of C. sinensis was described early by

IIJIMA (1886) and SAITO (1898) briefty. Later HIGUCHI (1938) dcscribed its morphology

in detail and con自rmedthe result of the observation by FAUST el al. (1927)

568

HIGUCHI (1938) al尽ostudied 011 the development of the !arvae of C. sinensis

in P. manchQur;cu$ experimentally. Snails weγe put into an aquarium containing

numerous eggs of C. sinensis. These snails were confined in the aquarium for

18 hours. Then a specimen of snails was taken out everyday one by one and

examined

According to his observation the miracidia hatched in the intestine of snails

within 20 hou日 afterthe feeding and penetrated into the tissue of snails after

2 days. FAUST et al. (1927) found， however， that the miracidia hatched in the

oesophagus of the snail and penetrated the wall of its intestine

Regarding the time able to obtain sporocysts in the snail after feeding

with eggs， NAGANO (1925) could find a spoγocyst and several rediae in the

intestinal wall of snails 29 days after feeding. FAUST et al. (192ηwere able to

get the youngest sporocyst twenty days after feeding. But through the

observation made by HIGUCHI (1938) young sporocysts were shown in connectIve

tissues along the wall of the esophagus 5 days after feedIng. It is round in

shape and is distinguished from the host tissue by its membraneous wal1. The

germ cells in it are found divided vigorously. HIGUCHI could observe sporocysts

in almost all snai1s 7 days after feeding

2. Redia

According to HIGUCHI (1938)， the redia was found in the connective tissue

around the posterior part of the esophagus， In that neiboring the wal1 of the

stomach and reproductive organ of snai1s 14 days after feeding. In these rediae

a pharynx and a primitive gut were already differentiated. And they contained

germ balls of cercariae. He found rediae in al1 snai1s 17 days after feeding

On the morphological description of redia a report by KOMIYA et al. (1940)

is availahle. The redia of Clonorchis sinensis is sausage shaped; the size varies

according to the stage of development， the smaller ones measure ahout 0.352 mm

xO.088 mm.， the mature one approximately 1. 727xO.130 mm. A small suhterminal

pharynx is p町田nt，measuring about 0.022 mm. in diameter. Around its openIng

about 8 hairs are to be seen. They are supposed to be sensory hairs. A short

sacciform intestine follows the pharynx. It freQuently extends along one side

when the body of the redia is filled wIth cercariae. Very often irregularly

shaped， brownish corpuscles are observed in the intestine. Apparently they

are ingested liver tissue of the host. No glands near the pharynx can he

observed as in the case of 0か.sthorchisredia (VOGEL， 1934)

The cercariae in redia vary from 3.5 to near1y 50 in number， corresponding

to the

569

mas日 sscattered throughout the body. This fact indicates that the cercaria of

C/onorchis sinensis moves prematurely from its partl、enitato the liver tissue of

lhe host， as the other cercariae of pleurolophocerca groups do. KOMIYA et al

noticed many premature cercariae of C. sinensis are， with taiJs which have been

just forrned， present free in the liver tissue of the host. They found as well

that on examining the mature redia under the microscope sometimes such

immature cercariae were pushed out one by Qne from the redia near the end

of the intestine. The description of redia differs from that by FAUST el al

(1927) in having sensory hairs on the cephalic end of the body， and having no

pigment in the body， and containing approximately 50 cercariae when mature

KOMIYA et al. (1940) pointed out that the description by FAUST et al. was

erroneus

Concerning the excretory system of redia， KOMIYA et al. made a follow同 g

description. A pair of担 paratedexcretory systems is present extending from

the end of the intestine to the posterior extremity one on each side of the bOdy，

their main collecting tubes opening outside separately. In mature redia fifteen

or more f1ame cells forming two groups were present on the both sides of the

body

3. Cercaria

On the morphology of the younger cercaria of C. sInensis the report by

FAUST et al. (1927)・isavailable

Regarding the morphology on the mature cercaria MUTO (l920b) described

very briefly. More detailed description was made by YAMAGUTi (1935) and

KOMIYA et al. (1940). The following description is based chiefly on the studies

by YAMAGUTI and KOMIY A et al

The body is 0.216 mm. -0.238 mm. long and 0.062 mm. -0.092 mm. wide

The surface of the body is covered with minute spines. Six long and 7 short

配 nsoryhairs are pr回 目ton the body laterally. Throughout the bOdy， masses

of brownish pigment are scattered and a pair of eyespots is present in the

anterior one third of the body

The oral sucker measures 0.040 x O. 022 mm. -0.045 x O. 031 mm. in diameter

It has small teeth like appendages on the dorsal part of the mouth opening

They are arranged in four rows; the number of the most ventrally located

being 4. The acetabulum lies between the penetration glands and the excretol'y

vesicle. lt is laterally ellipsoid in shape and is about one third of the oral

sucker in size. The pharynx lies a little below the eye-spot and measures 0.011

• The description by FAUST el af. (1927) on the CloJlo/'chIs cercaria was erroneus in several pomls

570

mm. in diameter. Seven pairs of penetration gIands

0， are present， occupying the part of the anterior body

f. below the pharynx. Their ducts run up to the lower

'" 内 rimof the Ofa¥ sucker， where they afe divided into

雷、

c.t

Fig. 4. Cercaria of ClonQrchis si1/fnsis (KOMIYA el al.， 1940)

Bg: penetration gJand C: cyslogen gJand Df: dorsal fin Ep: excrelory pore Esp: eyespot Exb: excretory veside Fc: flame cell Ga: genital "AnJage" 101; intestine 09: oTal sucker Ph: pharynx Sh 鶴岡οryhair Vf: venlral fin Vs: ventral sucker

two， !eft and right bundle and each bundle is diverged

into 2 bundles， the internal Qne containing 4 ducts

and the external 3. They open at the anterior margin

of the oral sucker

The genital anlage can be recognized as a compact

cell mass dorsal to the accetabulum. The nerve

commissure is observed beneath the pharynx. The

cystogenous cells are l4 pairs in number and are

arranged in a row dorsolateral1y on the both sides of

the body

The tail， with double length of bOdy， measures

0.374-0.488 mm. in length and 0.045-0.053 mm. 111

diameter and is covered with a transversely lined

cuticula over the whole surface. The cuticula swel1

conspicuously 00 the upper one thiγd of the taillength

00 its ventral side. A fin-like membrane can be seen

dorso-ventrally. Dorsally it begins from about one

third of the length of the tail from the joint， while

on the ventral side it commences a little more

distally (KOMIYA et al.， 19哨)

On the excretory system of the cercaria， KOMIY A

et al. (1剖 0)made a detailed description

The excretory vesicle occupies the greater part of

the posterior body. In shape it is a blunt cornered

inverted triangle or roughly speaking bluntly oval

Its wall is thick and consists of a layer of cells. The

main excretory canal starts from the upper corner of

the triangle and runs laterally upwards to the mid

body level， where it divides into an anterior and a

posterior collecting tubes. The anterior collecting tube

divid田 again;nto the two tertiary cOllecting tubes，

and posterior one into three， each of which is connected

with three flame c沼IIsby their respective collecting

capillaries. Thus the flame cel1 pattern of the cercaria

of Clcnorchis sinensis is 2 x ((3+3) + (3+3+3)) (KOMIYA

571

.el al.， 1940)

KOMIYA e/ a/. (1940) noticed that the dctail of the excretory system of the

cercaria of Clonorcllis sinensis is very di侃cultto lrace because of its fine structure

as well as of the existence of pigment masses scattered throughout the body

.Contrary to YAMAGUTI (1935)'5 figure Clonorchis cercaria， in which the mature

cercaria had an excretory canal in the tail stem， KOMIYA el al. pointed out

that 110 canal entering the tail can be recognized in the mature one in spitε

of the fact that in the tail no pigment mass is present. Recently INATQMI et

a/. (196ι) confirmed KOMIYA et al:s observation above mentioned using an

.electron microscope tcchnique

D. Shedding of the Cercaria frol1l Snails

Accord川 gto F AUST et 01. (1927)， the cercaria escapes from the redia in its

immature state and completes its development in the interhepatic Iymph space

of the host. The enveloping membrane of this region becomes burst because

of the mature cercariae in it and the cercariae remove匝 tweenthe bOdy of the

snail proper and its shell and after fully developed they emerge free into water

in which the host lives. KOMIYA el al. (1940) also confirmed such a fact

Prior to their observation above mentioned， ITO (1926) noticed that cercaria

shedded from snails at the temperature of 20・C-27・C，1. 5 hours after putting

them in water， and at 14・C-19・C，4-5 hours after putting， but no cercaria shedding

from snails at the temperature of 7・C-80C. He showed that the shedding of

cercariae was influenced by temperature. The shedding of cercariae was

observcd during several days hereafter

He slso described the activity of the cercarIa. It proceeds forwards rapidly

by mcans of the vigorous movement of its tail. After standing still for a while

it makes a similar jump again. At the time of standing still the cercaria

hangs in water with their body downward， bending its tail like a pipe. The

same behaviour was observed by YAMAGUTI (1935) and KOMIYA el a/. (1940)

The longevity of the cercaria of Clono町 hisin water is for 24 hours at the

lemperature of 12・じ270Cin average and for 28-29 hours at the temperature of

8・C-9・Cat the longest (ITo， 1926)

V. THE SECOND INTERMEDIATE HOST OF

CLONORCHIS SINENSIS AND THE

DEVELOPMENT OF THE LATTER

A. Diseovery and Species of Second Intermediate Host

1. The species of the second intermediate host

In spite of the discovery of the adult Clonorc1ds sinensis in relatively old

times (MCCONNEL， 1875) its life history has been little known till 1909

In 1910， KOsA YASHI found a kind of metacercariae in the muscles of fresh

water fishes， Leucogobio guntheri and Pseudorasbora parva. He fed cats with

these metacercariae and one month after feeding he found C/Qnorchis eggs in

feces of experimental animals， which were sacrified later and adult Clonorcllis

¥VQfmS were recovered from the liver

Later， KOBAYASHI (1912a) made a survey on the second intermediate host

naturalJy infected with Clonorchis metacercaria in Miyagi， Shiga and Okayama

Prefecture in Japan， and demonstrated that the following 12 species of fresh

water fishes belonging to the family of Cyprinidae as the second intermediate

host of C. sinensis. Pseudorasboraρarva (SCH.)， Le叫 ')gobiaelangaia (T. & S.)

(Syn. L. guniherj ISHIKAWA)， L. jaρanica (SAUVAGE)， Sarcachei/ichthys variegatus

(SCH.)， Pseudoteri!amtus ty.ρus BLEEKER， Parachei[ogna(us rhombea SCII.，

Acheilognatus lan曲 olala (SCH.)， A. limbola (SCH.)， A. cyanostigma J. & F.，

Pseudogobio rivularis (BAS.)，品ωio:zezera (ISHlt【AWA)and Corossi町四町四川(L.)

Since then many studies on the second intermediate hosts of C. sinensis were

performed by many Japanese woγkers in Japan， Korea， China， and Formosa

(KOBAYASHI， 1910a，b， 1912a， 1923， 1924a; OHOI， 1919; MUTO， 1917， 1919b; KOGA，

1922; ANDO et al.， 1924; K060町， 1927; ISHII， 1929b; lCHIOKA， 1930; SATOMI， 1931;

lZUMl， 1935; IDE， 1935a，b; KOMIYA el 01.， 1936， 1942; ASADA， 1937， 1940; NISHIMURA，

1938; OKABE， 1938b; MUTO， 1938; MIYANAGA， 1939， 1944; KUBO et 01.， 1941; SAKAI，

1953 ;日ORIUCHl，1956)

A list of the histhero recorded sεcond intermediate hosts of C. sinensis is

given in Table 1 and 2

It is to be noticed here that several older reports had mentioned names of

fishes in Japanese commonly used locally with no scientific names. Thus some

Scientific name

Table 1. The list 01 the second intermediate hosts 01 Clolwrchis suwllsis in Japan

573

Abゆ切れ1/(/ rivularis (BAS!LEWSKY)

Author

AcheifoglJa/lIs cyollQs/igma (jordan et Fowler) KOBAYASHI

KOBAYASHI

A. lal1ceola/a Im/ceola/a (T. et 5.)

A. 1. limba/a (T. et 5.)

A. 1. lIIoriokae (Jordan et Thompson)

A. rhombea (T. et 5.)

siw;a zeura (ISHIKAwA)

Carassius ca/'(/ss;us (L.)

KOBAYASHJ

KOBA YASIIJ

I-IORJUCHI

KOBAYASHI

KOBAYASHI

KOBAYASHI

Cytrinus cartio L 込1UTO

G即 r加ρogollelol1gaflls caemfesel1s(5AUVAGF.) ANDO el (1/

G. e. elOl申山IS(T. et 5.) KODAYASIII

G. e. gracilis (T. et 5.) OKABE

G. c. jatol1iws (5AUVAGE)

Hemibarb出向rb"s(T. et 5.)

Hemigra川 IIIOCY，ρrisrasborella FOWLER

HytOmeslls ofidlls (PALLAS)

Mogllruudo obSClfro (T. et 5.)

。ρsariichfh)'sIIncirosfris (T. et 5.)

p，制 dogobioesoci削 IS(T. et 5.)

PselldOterifamtus tytllS BLEEKER

PselldOlasbo/'(/ρr/rva (T. et 5.)

RhodeU5 ocel(llllS (KNER)

$orcocheilich/hys !/ariega/Ils (T. et 5.)

5i吋 obiobi附 eυORDANet臼 YDER)

Tribolodoll h(lkollellS;s GUNTHER

ZaccoρlolyρIIS (T. et 5.)

Z. lemlll作品cki(T. et 5.)

KOBAYASII!

10' Izu~!1

10'

KOCA

5ATOMI

KOsORJ

K08AYASHI

KOBAYASIII

OKABE

KOBAYASHI

5AKAl

I印 IOKA

MUTO

Izu~1I

幻

nmwm一旬

町

的幻山町川町叫期間同

町

閉

め

り

η問

的

問的勾仙川

η間

9

9

9

9

9

9

9

9

倒的U9999mm9mm田

mM99広

引

防

犯

引

航

t

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

l

u

r

-

:

1

(

(

(

(

{

{

(

{

{

{

(

{

{

(

(

{

(

{

{

(

(

{

{

{

(

(

(

Lo四 lity

Okayama

Okayama

5higa， Okayama

5higa， Okayama

Akita

5higa

Okayama

5higa

Okayama

5higa. Aにhi

Okayama， 5higa

Fukuoka

Okayama

Ibaragi

Hyogo

Ibaragi

Kumamoto

00担 k.

Aichi

Miyagi

Okayama， Shiga

Fukuoka

Shiga， Okayama

5higa

Toyama

Shiga

Hyogo

of these fishes were not able to be identified. Such fishes were discarded from

the table. On seeing the table it is clear that most of fish田 servedas the

second intermediate host of Clonorchis sinensis belongs to the Family Cyprinidae.

except those belonging to the Family Gobiidae， Osmeridae and Ophicephalidae.

KOGA (1922) found the metacercaria in Mogurunda obscura (Fam. Gobiidae)

from Kumamoto Prefecture. Later no report on this fish as the second

intermediate host was recorded. It is uncertain whether this fish is incriminated

as the second intermediate host of C. sInensIs

IOE (1935b) found the metacercaria in 的向mesusolid町 (Fam口smeridae).No

workers recorded this fish as such later

The records of FAUST et al. (1927) and KUYAMA (1938) were discarded from

the tab!e because of the possibility of their taking another metacercaria for that

of C. sinensis

574

Table 2. The list of lhe second intermediate hosts of

ClOllorchis si"ellsis in China， Formosa and Korea-

Sdenlific name Author Locality

Abbotina riV/floris (sAS1I.EWSKV) KOIIAYASIIl (1923) China:品位how

KOBAYASIII (1924) Korea

ACOlltf，obr(llll(l simoni BLEEKER KOM!YA (1944) China: Hankow

Acanlhorhodeus aS/JI!lssi DVBOWSKl ASADA (1倒的 China: Mutan-kiang

A. alranalis GUNTHER KOBAYASI¥I (1923，24) China: 50田 how

A， grot:ilis REGAN KOBAYA5Hl (1924) Korea

A. faCIII(wa{is GUNTIIER CHUNG et aλ (1960) China: Peiping， Tientsin

Athyocytris chimlllsis (GUNTIIF.R) ASADA (1940) China: Tiehling

ε。rassillscarassius (L.) ISHII (1929) China: Canton

ε'ltmoplwryngodon idelllls (C. el V.) 01101 (1919) Formosa

ISIlH (1929) China: Canton

ClIller albllnws BAS11.F.WSKY KOM1YA et al. (1936) China: 5hanghai

N!SH!MURA (19羽) Korea

C. mOllgoliclIs BASILWSKY ASADA (1940) China : Tiehling

ClllleriClIIlIS hwri (WARPACIIOWSKI) MUTD (1938) Formo姐

CytrInllS cortio L. ISHlI (1929) China: Canlon

EleotrIs swi.thollis GUNTHt:R CHUNG cl 01， (1960) China: Peiping

ElotichthJ's bombllso (R!CHAROSON) KOMIYA et 01. (1936) China: 5hanghai

Cnothotogoll coreOlIl<S BERG KOBAYASIII (1924) Korea

G. herZClIslcini GUNTHER Hsu el 01 (1930) China: Peiping

G. polytaellio (N!CIIOLS) KOMlYA cl 01. (1942) China: 5hanghai

C. slrigoll<s REGAN KOBOYASIII (1924) Korea

ASAOA (1940) China: Tiehllng

Cobio gobio (L，) ASAOA (1940) China; Mutan.kiang

fI. lOllgirosl，.is REGAN NIS!IIMURA (19謁) Korea

H刊 liborbllS川 oClIlatusBI.EEKER Hsij el 向上 (1936) China: Peiping

HcmiC/IlIer C/IIρcoidcs NlCIIOLS HsO el al (1936) China: Peiping

fI. lellciswllls (BAS!LEWSKY) Hsu cl al. (1936) China; Peiping

l1y釦'thlftal川 ichthys問。lilrix(C咽 etV，) ISHIl (1929) China; Canlon

fI. IIobi/is (RlCIIARDSON) TSIIl! (1929) China: Canton

Lobeo col/oris NJCIIOLS el POPE HsO el (.d， (1931) China: C且nton

L. kOlltills jERDON ISIIl! (1929) China: Canton

品1ylotltary"godolloethiots (BAS1LEWSKY) Hsu cl al. (1934) China: Canton

0ρIliceρJtafllS orgllS CANTOR ASADA (1931) China: Harbin

ParaμleclIs eigellll101l11i JORDAN el METZ KODAYASIJ! (1928) Korea

P. Il1IIgcJlowe>lsis TCIIANG CIIUNG el 01. (1960) China: Peiping

P. orgelltclIs GijNTIIER KOM!YA el 01， (1936) China: 5h且白ghai

Parabramis broJ/llllo (ιel V.) HSO el 01 (1934) China: Canton

Porac/tdlogllotlws ，.llOmbea (T. et 5.) NtSHtMURA (1938) Korea

Psetulorasboro tor/Jo (T. et 5.) KOBA YASllt (1923) Chsm。oachShanHgahn ai， ow， Hangchow

KOBAYASHJ (1924，25) Korea

51.

l'utlJungia Iltrzi HERZI!NSTEIN NISHJMURA (19羽) Korea Rhodeu$ nO'"II/$ NrCHOLS 島11YANAGA (1939) China: Mukden R. OCellalllJ KNI!R H吉tiel al. (19謁} China: Peiping R. str;ceu$ (PA1.LAS) ASADA (1940) China: Mutan-kiang Sarcocheilichrh)'j kQ白川sM;MORI KOBAYASHI (1928) Korea S‘ laC/ulris DYsDWSKI ASADA (1937) China :HaMrbu in，

lan-kiang S. 1110/"; jOIl.OAN et Hun白E KOBAYASHl (1924) Kore且

S. I，;grip;，wis (GUNTHI!R) KOM1YA 61 01. (1936) China: Shanghai S. sinelUis BI，F.I!KI!R KOBAYAS!II (1924) China:ShaSn剖gEchhaoi，w

S. soldalovi BI!RG ASADA (1937) China: Harbin S. variegall/S (T. et 5.) KOBAYASHI (1923) China: Shanghai

KOBAYA5Hl (1924) Korea S削 'Irog()/)iodabri BLI!I!KI!R KUBO r;f al. (1941) China: Chahar Squtlliob(ll'blfS cllrrIcufns (RICHARDSQN) H50 el (/1. (1936) China: 50侃 howTilatIa IIIossamoica (PETERS) CUQW (19伺} Form(拘昌

• After the World War 11， following fishes were newJy recorded as the second intermediate h。針。fC. ulle旧日 by LEE el 01. (19泊)and KIM (l鏑1)川 Korea，but with neither figure nor photograph of hosts and metacercaria in texts: lIisllo elongola 田ennet)(L田 elof.， 1958)， PselldOterifam帥 S帥 lollls B1~ker (LEE el 01.， 19剛，AcheilogllOlllS slKni!er Berg(K川 ，19611，A. )"omolslS/lloe MORE{KIM， 1961)， Core，拍 1rgllsbrerII印巾叫C.etV.)(拍 M，1961)， Hemi加rbllSlobeo PALLAS (KtM， 1961)， Microtlt)"sogobil 削 reensisMORI (K刷， 1961) and So何 oclleiliclltll)"swoki)"oe (KtM， 1961)

ZacCQ tlalytus was recorded as the intermed凶 tehost of C. sinensis by MUTO

(1917)， SAKAcucm (1956) and HAYASHI et al. (1957). But according to the records

of many olhcr川 vestigatorsthis fish was never been found nalurally harboured

ClQ110rchis metacercaria (lZUl¥1I， 1935; OKAsE， 1938b; KANF.MITSU el al.， 1953;

KOMIYA et al.， 1950; SAKAI， 1953; OOTSURU el (11.， 1963). Whether this fish can

serve as a natural intermediate host of C. sinensis is to be studied further

Regarding Otllicethalus argus， ASADA (1937) found ClO1!orcltis metacercaria in

it from Harbin. Later KUBO el al. (1941) examined a large number of Q. argus

in Manchuria， but no凱 ngleca田 wasfound harboured the Clo1!orcltis metacercaria

Al about the same time ASADA (1941) recorded another case of Oþhic~ρhalus

naturally infected with ClOllorchis metacercaria from the River Sungari in

Manchuria. KOMIYA el al. (1949) examined a number of O. argus in Shanghai

and found only one case infected with ClOllorchis metacercaria. But they

mentioned that the metacercariae found in this fish was small in size and p∞dy

developed. At any rate the natural infectioll of Clonorcllis metacercaria in this

species of fish appears to be extremely rare

2. The density of metacercariae among various kind of fishes

KOBAYASHI 0912a， 1922) noriced that among species of fishes obtained from

the same area， the average number of Clonorchis metacercariae varied remarkably

576

He considered that the reasons might be attributed particular1y to the extent

of cercarial invasion and development in fishes

MUTO (l919b) experiロentallyInfected Clonoychis cercat-ia to P. parva and C

cα叩 ssiusunder the same condition. The result showed that P ρarva had be叩

heavily Infected with its metacercaria， whereas in C. carassius ClQnorchis

metacercariae had been found very few in number. MIKI (1922) took off a part

of dorsal skin of C 回叩'"附，Cypri附 scarpio and Pρarva and put them together

with vector snails shedding ClQlIorchis cercaria. The results showed that many

Clonorchis metacercariae were found in P ρ'arv.α， whereas in C. carα'ssius and C

mrρio no metacercariae were found. The same results were obtained among the

control group of normal I1shes. Then he injected ClonorcJzis cercariae into the

suhcutaneous lissue of C. carassius and C. carρIo. All cercariae were found a¥ive

in flesh of these I1shes just after injection. But， in the course of time， in these

fishes they were prominently reduced in number and only a few metacercariae

were able to be recovered. In gold fish， 00 pr田 enceof the metacercaria were

observed， wheras in P. parva used as a control many metacercariae were found

infected. From the ahove reslIlts he conc¥l1ded that the penetration and the

development of Clonorchis cercaria in fishes would depend upon the specific

nature of fishes

B. 'l'he Developl1H':nt of Clonorchis l¥1etacercaria in 日開 SecondIntermediate

Host

1. Infection experiment of the second intermediate host with ClOllorchIs

cercanae

According to the results of KOM1YA el al. (1940)， the cercaria hanging in

water does not attack the I1sh host by its own accord. In the course of repeating

its characteristic movement， when the cercaria come into contact with the body

of the fish， it attaches itself instantaneously to the body of the fish with the

penetration organ， raising its tail perpendicularly to the body sllrface of the

fish host or extending it parallel to the latter. Then it adheres to the body of

the host with the whole ventral sl1rface， elevating somewhat the dorsal part of

the body， and making a sort of creeping movement， and tries to enter the host

body. The tail falls off spontaneouly in most cases two or three minutes after

the cercaria attaches itself to the body of the host. The place most commonly

invaded appeared to be the trunk of the host. The cercaria which iovaded

the fins removed centripetally along the long axis. Usually it takes about ten

minutes or more for a distance of some 5 mm. ln ordinary cases it la

577

within the fish body and pointed out that the most favorab!e area was its

muscl田 suceededby the soft tissue of the head. They considered that the high

incidence of Clonorchis metacercariae in the latter would be attributed to the

fact thal the cercariae were sucked into the mouth of白shwith water and

invaded the surrounding tissues through the oral mucosa

2. The devo!opment of metacercaria in the body of fish

On thc devc!opment of

Clonarchis metacercaria in the

間 cQnd intermediate host， the

delai1ed study by KOMIY A el al

(1940) is availab!e. They

observed the development of

the metacercaria in P ρarva

1，3，7， 10， 15 and 35 days after

being infected (Fig. 5)

The cyst of the meta

cercariae twenty four hours

after the infection measured

0.0836-0.11曲 mm.in diameter

and already had a second cyst

!ayer produced by the host

itse!f， which measured ca. 0.0018

mm. in thickncss. The wall of

the cyst produced by the worm

ilseJf mcasures about 1. 8μ

The mctaccrcaria in it was

found to be contracting its

body along its long axis. It

looked brownish in color owing

A e

c D

Fig. 5. Developement of rnetacercaria of CI()lIorcllis "肘nsisin the second interslediate host. A. 24 hours after infection; B. J da)'8 aher inr~割ct lOn:C. 7 days after infection: D. 15 days aher

to the pigment masses scattered infection. (Ko州 YAtl al.， 1940)

throughout the body. The pigemented eyespots showed no sign of di田 ociation

As a result of the both facts mentioned above the metacercariae at this stage

of developmenl showed their characteristic features

The oral sucker has already lost its penetrative nature and made 比目!fas a

true sucker. The acetabulum was not yet well develo問 d. The intestine was

Ilot yet recogn山 ble. The excretory vesicle was obscrved as a bluntly shaped

oval sack having a thick wall. It contained only 20-30 small and irrcgular

excretory corpuscles as yet. Many smaU corpuscles， probably consisting of fal，

were seen throughout the body. The me回目rcariaeat this stage of development

578

were in the process of metarnorphosis

The elliptica! cyst three days after the infection measured approximately

0.114-0.084 mm. X O. 13CドQ.108mm. in diameter. The pigmented eyespots were

sti1l present in the metacercaria at this stage of development. The pharynx，

intestine， and acetabulum became more c1early v山 ble.The excretory corpuscles

in the bladder increased in number as well as in size. However， on the whole，

the worm was stil1 in the process of metamorphosis

The cyst seven days after infection measured 0.119-0.092 mm. xO. 141-0.101

mm. The metacercaria in it was found folding its body two times. The

eyespots began already to di日 ociate.The excretory corpuscles削除dthe vesicle

almost completely. In the intestine many round disc shaped corpusc¥es began to

appear. H。、vever，the oral sucker as 、vellas the acetabulum were not yet

perfectly developed. At this stage of development the former was still larger

than the latter

The cyst ten days after infection measured about 0.132-0.097 mm.xO.141-

0.110 mm. Now both suckers were fairly well developed， and the excretory

corpusc¥es large as well as small，自lledthe vesic¥e completeJy. Metacercariae

in alJ the stages of development above mentioned died when acted upon by

artificial intestinal juice for twenty minutes at 37・cThe metacercariae fifteen days after infection measured 0.123-0.092 mm. x

0.141-0.097 mm. Now the metacercaria in the cyst was found foJding its bOdy

two or three times. (t made a vigorous rotatary movement intermittently. At

this stage of development the characteristic structure of the metacercaria was

complete. The eyespots were found compJetely dissociated; the acetabulum

became larger than the oral sucker (the former being 0.04-5 mm. and the Jattel"

0.0436 mm. in diameter respectively); the pharynx measured 0.0252 x O. 0216 mm

The larger excretory corpuscles attained to 7.2μin size. The disc like corpusc¥es

above mentioned appeared numerously now in the intestine. After acting

act同cialintestinal juice on cysts at this stage of development for thirty minutes

at 37・c.5 among 36 were found liberated from cyst and alive

Thirty five days after infection the metcercaria was found well developed，

its acetabulum became larger than the oral sucker. Now the former measured

about 0.066 mm. in diameter， while the latter m田 suredsome 0.048 mm. in

diameter. It should now be regarded as a mature metacercaria. However， when

the melacercariae were fed to a mouse， no adult ¥Vorms、，vererecovered thirty

days after feeding (KOMIYA et al.， 1940)

It

579

in the beginning of August. NAGANO (1936)， after suc!:essive experiments

confirmed that within a period of 23 days after infection of P. tarva with

cercaria no adult worms were recovered

The de日screpancybetwecn the results above mentioned would be attributed

to the different temperature of the environment during the course of experiment

3. The distribution of metacercariae in the fish host

KOBA Y ASHI (1922) found the majority of encysted metacercariae in the

connective tissue and in the muscle near the skin. In muscle layers far apart

from the skin they were found less in number. KAWAI et al. (1935) investigated

the distribulion of Clonorcltis metacercariae in six P. tarva which harboured

them 1，939 in average number and reported that they were found mostly in

muscles of fishes. His results showed that 47.4 % of their total number was

found in muscles， 26.6 9杉山 heads，16.8 % in skin and subcutaneous tissues， 5.2

% in fins and 0.7 % in scales. IWATA (1937)， divided fish body into the

subcutaneous tissue， superficial muscle and inner muscle， and recovered Clonorchis

metacercariae from each portion. The result showed that the rate of the

Table 3. The distribution of CIOl1orchis metacercariae in Ihe fish body (KOMIYA et al.， 19凶0，19014)

F時 h(No. examined) P. par四 (40) P. pan.・.(j (15) s. 5iJte"sis (15)

Lxation No. of metacercai日 No. of metacercaria No. of metacercaria found (弱} found (%l found (%)

Scales 5 ( 0.2) I ( 0.3) 169 ( 1.6)

Gilles 16 ( 3.6) 13 ( 3.6) 125 ( 1.2) Tail fin 185 (10.自〉 3 ( 0.8) 651 ( 6.2)

D"回 1fio 12 ( 0咽 7) o 300 ( 2.9)

Breast fins 11 ( 0.6)

Ventral fins 3 ( 0.2) 1 ( 0.3) 324(3.1) Other fin 。Muscles 1. 328 (77. OJ) 320 (87. 9) 6，616 (63.4) Head 155 ( 9.0) 26(7.1) 2.250 (21.6) Inner organ 。 o 。Total J， 715 総4 10，435

incidence in the subcutaneous tissue was found highest (71 %)， followd by those

m super白cialmuscle (15 %)

KOMIYA et al. (1940， 1944)examined the distribution of Clonorchis metacercariae

in bodies of various fishes (Table 3). As seen in the table， metacercariae were

found mostly in their muscles and particularly in the posterior bOdy following

the tail白n，as pointed out by HsO et a/， (1936)

580

c. 'l'he Metacercaria of ClQlIQrchis sinensis

1. Morphology of the mature metacercaria

The metacercaria of ClonQTchis sinensis has been described briefly by

KOBAYASHI (1912a， 1922) and more in detail by HsO el al. (1937) and KOMIYA el

al. (1940)

The cyst of C. sinensis is oval in shape， measuring aboul 0.135-0.145 mm. x

0.09-0.10 mm. (KOBAYASHI， 19叩)

According to KOM1YA et al. (1940)， the liberated metacercaria is spatula-like

in form， tapel'川gslightly towards the posterior part of the body. lt measures

apporoximately 0.406 x 0.121 mm. and makes vigorous leech-like movements

When extended， the anterior half of the body attains about twice its length of

the posterior part of the body. The body surfac巴 isbeset transversally with

the small sp目的， which extend all over the body surface except for a smal1 area

on the dorso-anterior part of the body， mouth opening and acetabulum. These

spines become finer at the posterior part of the body. The sensory organs are

small papillary projections， surmour】tedby a short hair， and are fo山ldlaterally

on the side of the body， usually 14-16 in number

HsO et al. (1937a) observed that 12 papillae were found around the oral

sucker forming two circl回目milarpapillae， nine in number， were found on the margin around the acetabulum. They regarded these as sensory organs

Numerous masses of brownish yellow pigments are found scattered

throughout the body. Both suckers are round in shape. The oral sucker measures

about 0.049 mm. in diameter and is smaller than the ventral one， which measures

about 0.062 mm. in diameter. Following the oral sucker a short prepharynx

and an oval-shaped pharynx are present， the latter measuring 0.020xO.018mm

The oesophagus is relatively long. lt bifurcates medianly at a point between

the pharynx and the anterior margin of the acetabulum into intestinal branches，

which run along the side of the body up to its posterior end. Many'disc-shaped

corpusc¥es are observed in the intestine. They move to and fro as the worm

moves. Two kinds of glands， skin glands and cephalic glands， are present

The skin glands are found， arranged in a row， on the surfaces of the anterior

part of the body， numbering about 24 in all. Ordinarily their arrangement is

as follows; one lateral to the oral sucker; one lateral to the pharynx; six

laterally， in the area between the pharynx and acetabulum; three near the

oesophagus and one on the upper margin of the acetabulum， respectively， on

each side of the body. They all open ventrally to the exterior. The cephalic

glands are found

where they open externally. The transversal

nerve commissllre is found medianly under the

pharynx. lt rlll1S up to its posterior end. The

genital primordia call be seen in stained

speclInens as 、vell in living materials. The

testes primordia are recognized as small bal1s

obliquely sitllated， QneS on each side of the

excretory vesicle. The ovarian complex is

fOll¥ld in the midline between the acetablllllm

and the excretory vesicle The uterus

primordillm is recognized as a cord extending

from the ovarian complex to the mediall upper

margin of the acetablllum

The excretory vesicle occllpies the greatel

part of the posterior part of the body. lt is

blllntly oval in shape in any instance and is

ftlled wilh numerous excretory corpuscles

They have compact outlines and are spherical

or bll1ntly oval in shape， ranging from 0加9

0.0018 mm. in diameter. Owing to their

refractive nalure they appcar almost black

under the ordinary microscope. WATANABE

(1942) reported that thesc corpllsc!es consist

of calcium carbonate and calcium phosphate

As for the excretory system of Clonorchis

metacercaria， KOM1YA el al. (1940) also made

a detailed description. The main excretory

canal starts from the lIpper lateral corner of

the excretory vesicle and proceeds upwards

with several coils， a!ong the ol1ter margin of

the intestine， and on attaining the level of

approximately the uppcr half of the acetabllll1m

it is divided into the anterior and posterior

collecting tubes. The former proceeds upwards

and then is divided into two branches， each of

which has three flame cells with their respective

collecting excretory capillaries， The posterior

collecting tllbe proceeds downwards parallel to

the main excretory canal， and after scnding

581

Fig. 6. Metacercaria of CloJ/ol"chis simJ1lsis {KOMJYA el (11.， 1940)

Cc: central nerve commissure Cg: cephal犯 glandEp: excretory pore Exb: excretory v(!sic1e Exc: excretory canal Fc: Hame cel1

Ga: genital "Anlage' In1: intestine C回目鈎phagusOs: oral sucker Pg: pigment mass Ph: pharynx Sg: skin gland 50: sensory organ T: testis Vs: acetabulum

582

one branch upwards at the level of the upper end of the main excretory canal

it is divided into branches. Each of these three branches has three f1ame cells

with their re日spective excretory capillaries. Thus the ftame cell pattern is

represented by the following formula: 2x (3+3)+(3+3+3) . which is just the

same as that of the cercaria

2. Resistance against chemicals

SH1MAZONO a al. (1916) examined the resistance of Clonorchis metacercaria

against various chemicals， and the result of which is shown in Table 4

KOB.....YASHl (1922) put the fish ftesh containing CIQnQrchis metacercaria into

vinegar or soy bean sauce for five hours， but the metacercariae were found still

alive. KAKEl et al. (1921) also found il alive in vinegar for 4 days. but found

Table 4. The陀 sistanceof CloJlorrhis silll!lIsis againSl the various chemicals (SHIMAZONO CI 01.. 1916)

Name of Survival tlm世

medium 。fmetacercaria Tap water 54 hours

Saline solution (5%) 3 hours

5 hours

Lugol solution :) mmutes

Methlene blue (l~副 4 hours

Eo宮ine(0.7%) 1 hour

Me:tanol 10 mInut出

(1%) 20 minutes

( n{lO) 2 hours S剖liumhydroxide

( n/15) 2 hours

Cyst wall intact

Cyst wall intact

Cyst wall deslructed after 10 minutes and the larvae died after 20 minutes

CySI wall softened after 5 minutes. wall broken after 17 hours and lar四 eliberated after 19 hours Cyst wall broken after 19 hours and active larvae were liberated but found dead叩

sゆdiumcarbonate {lO%l 19 hours

( 1%) 21 hours

(0.5%) 48 hours

C

a

n

a

v

s

y

c

-

-

Diluted hydrochloric acid (20%) 2.5 hours (nβ24 hours

(n/10) 48 hours

Dilutec! acetic acid (39的 6hours

dead after 6 days; it was found in soy.bean sauce for 3 days and in saturated

saline solution for 2 days

3. Resistance against dessication and heat

SHI:-VIAZuNO el al. (1916) observed the aClivity of the encysted metacercaria

on exposing it without water under the room temperature. The result showed

that the activity of the encysted metacercaria was markedly diminished after 3

583

hours and no activity was recogr羽田dafter 7 hours' exposu:-e. They also e治:amined

the effect of heat 011 its viability and indicated that it was killed for 3 minutes'

exposure al a teη1perature of 65・Cand for 2.5 hours' exposure at 39・c.0・cMUTO (1921) showed that in certain cases the cysts of C/QnorcJtis， after

日 paratingfrom the flesh of decomposcd fishes， fell into water and remained

viable for 5-12 days. Is11lI el al. (1935) domenstrated thal， within 24 hOU，.5 after the

cyst became separated from the decomposed fiesh of fishes in water， the

metacercaria remained viable for 48 hours. And they found thal the encysted

metacercariae survived for 3 to 7 days in the lissues of the dead I1sh. They

could obtaiI、theadu¥l ¥VQrm from the rabbils experimentally fed with slIch fish

4. Effect of digestive juice on metacercaria

SHIMAZONO el 01. (19l6) put fish flesh containing Clonorchis metacercaria into

gastnc J山田 obtainedfrom men for 17-18 hours. The results showed that the

activity of the eilcysted metacercariae. after separating from the flcsh， slightly

diminishcd. NAGANO (1927) applied an artificial gastric juice (HCI ; Icc， watcr;

I回 cc，pepsin; 0.5 gr.) for 3 hours undcr the temperature 39・C for obtaining

the encys1ed metacercariae from the fish 何回h，and he reported that the

metaccrcariae wcre able to 町 coverstill alive. KOMIYA ct al. (1944) also applied

an artificial gastric j山田 (dilutedHC1; 3.0 cc. distil1ed water; 1曲 cc.pepsm;

0.3 gr.) for 3-4 hou同 atthe temperature ca. 37 C for collecting the viable

maturc encystcd metacercariae from the flesh， and gained a good result

SIIlMAZONO el a/. (1916) kept the encysted mctacercariae in rabbits' bile juice

(or 1he bilc juicc dilulcd with physiological salinc solu1ion 01' with water) for

2 -20 hours in an incubator at 37・C. His reslllt showed that a few cysts were

softened and metacercariae were liberaled， bu1 the majority of metacercariae

was no1 able 10 be liberated from the cysts. At the same time， they fed dogs with the fish ficsh containing encysted metacercariae and disscctcd them 5 hours

l.¥fter feeding. They found the excysted metacercariae in its in1estine， but not

in the slomach. From this fact， they considered tha1 no excystation would take

place in the slomach of animals. but the metacercaria wOllld be liberated in

the intestine

KOMIYA el 01. (1941) applied， after exposing them to the effect of the gastric

juice above mentioncd， the artiticial intest‘nal iuice (Nalrium bicarbonate; 0.2 gr trypsin; 0.5 gr.. physiological NaCl solution; 50.0 cc.) for ahOllt 30 minutes

at the

VI. DlFINITIVE HOST

A. 1'he kind of definitive host

Soon after the discovery of the臼ukein men in ]apan， ir was found in dogs

(KATSURADA， 1892)， cats (llJ1MA， 1886)， pigs (the discovery from the pig in ]apall

by ]ANSON was described by LOOSE in 1907)， and Raflus norvegicus norvegiCIIs

(MUTO， 1920c). KOsAYASHI (1912a) demOl1strated that cats， dogs， rabbits and

guinea pigs were experimentally slIsceptible. Later EcuclII (1925) reported that

a camel bred in a zoo lVas positive for Clonorchis eggs

The infectiotl of C. sinensis in birds was first observed by ASADA (1920). He

examined 6 Nycticorax nic/i，叩 raxand found in one of them 13 specimens of C

sinensis harbouring in its gall bladder. He fed N. nycticorax and Anas dome山田

町..ithPρarva and C. carαssius harbouring CfonOTchis metacercariae and the adult

ClonoTchis was found in them though small sized. But he reported that phcasants，

crows and ducks experimentally infected with Clonorchis metacercariae were not

able to harbour the adu¥t自uke

KOM1YA el al. (1949) eventlla!ly fOllnd in one of seven Anas domestica 17

specimens of C. sinensis in the gall bladder. But those A.ukes were smal!er in

size than those naturally found in cats and dogs. An experimental infection of

A. domeslica with C/o削 Tclzismetacercaria proceeded by them， however， was not

successful. In view of the above mentioned findings they concluded that A

domesfica was not considered as an suitable definitive host of C. sineげlSIS

The work of KAWAl et al. (1935) is worth to be mentioned here. They fed

rabbi旬、 dogsal1d cats with the same number of ClonOTchis metacercariae and

found cats showing the highesl incidence. According to Wn<OFF (1958)， rabbits

and guinia pigs were found to be equally susceptible with this A.uke， about one

third of the orally administered metacercariae developing to matul"Ity， but rats

are less susceptible， showing only 6 % of the fed metacercariae became adult

B. Invllsion into Defi・nitiveHost

1. Route of migration of larva

In order to ascertain the route to はshabitat in the host， KOB，-¥YASHl (1912a)

fed cats with fish 何回hα川 tainingencysted metacercariae and on dissecting

them 15 itnd 24 hours after feeding， free yOllng A.ukcs were fOllnd both in the

585

gall bladder and the bile duct

MUKOYAMA (1921， 1922) fed rabbits with raw fish containing viable encysted

metacercariae and di田 ectedthem at certain intervals after feeding. He found

young flukes in the bile passage after 6 hours in case of rabbits. With the

lap田 oftime， the flukes made an increase in number. Ten to fourty hours aftel

feeding a large number of flukes were noticed in the liver and bile passage

He also confirmed the location of nukes in rabbits at given intervals after

feeding. The results arc shown in Table 5. He also gained the same results

in the casc of dogs and guinea pigs

TabJe 5. The site of C 刊 'leIlS;Sin rabbits al intervaJs foJJowing infection (MUKOYAMA， 1921)

Time after feeding

Within 5 hou悶

10-16 hours 20 hours

35 hours

Sile where found価ukesm伺'"In inteslIne， a porlion about 50 Cffi. be10w pyJoric region 1"・ntestme，a p。同胞nabout 30-40 cm. below pyloric regi削

Tn int舗 tine，a portion near the opening of the bile duct and the duodenum In intestine. a回 rtiona回以 10-20cm出lowpyloric region

Eventually the larvae， which excysted in the intestine. were found in the

fairly lower part of the intestine， but the majority of the young伺ukemigrated

from the duodenum through the common duct directly into the bile duct. He

then ligated the ductus choledochus of rabbits immediately after feeding them

with metacercaTIae and examined their thoracic and abdominal cavities， bile

passages， duodenum， and livers for flukes twenty hours to nine days after feeding

A large number of young larvae remained in the duodenum， while no larvae

were recovered from the other organs. Thus he concJuded that after liberation

Clono町 hismetacercaria is incapable of penet悶 tingthe intestinal wall of the host

Furthermore he encJosed liberated metacercariae in the abdominal cavity of

rabbits. but 110 fiukes were observed in the liver， bile passage， thoracIc cavity

and intestine from 46 hours [0 24 days after enclosing. From the result oblained

he concluded that the metacercariae migrated from the duodenum through the

common duct direclly into the bile duct

WYKOFF et al. (l田7)'sob盟 rvation，howev町 isnot in agreement with tho担

of MUKOYAMA (1921). They ligated the ductus choledochus in one group

of eXT泥Tlmen回 1rabbits and in another group applied a tube 針。m the gall

bladder outside for drainage. Then both groups of rabbit were fed with Clonorchis

metacercaria. After dis担 ctionyoung fiukes were obtained from the liver in both

cases. Their results indicated that Clonorchis metacercariae、、.'erecapable of

I問、etratingthe intestinal wall of rabbits and making their way to the liver

586

2. Site of worms in the defin山 vehost

The usual habitat of the f1uke in the host is the hepatic ducts， occasional1y

the gall bladder and the hile duct can serve as its habitat. 10 回目 ofhaving

fairly numerous fluk目。 mostof them are found in the perpherial fine hepatic

duct and only a few in the gall bladder. In heavy infections in the pancreas

and in the duodenum flukes could be found. They were apparently in good

condition (KOsAYASHI， 1912a)

1n the survey of the site of ¥VQrms in the bOdy of the rabbits， IWATA (1937)

showed that in heavy infectiol1s 77.4 % of a¥l自ukeswere found in the livcl

21.5 % in the bile duct， 1.8 % in the gall bladder， and in mild infections 96.3

% of flukes in the liver， 3.4 % in the bile duct and 0.3 % in the gall bladder

In all cases the majority of worms was found in the ¥iver. Among 100 cases of

the rabbits infected experimentally， ARIYOSHl (1930b) observed in 22 cases f1ukes

in the pancreas， and in 4 cases of dogs found them in the pancreas in all

cases. YOSHIDA (1931) observed that the young flukes actively invaded the

pancreas to deve!op up to adult in it. And he confirmed that the young flukes

showed positive chemotaxis to the pancreatic juice， but they were attt'acted by

the bile juice more intensively. YOSHIDA (1931) utilized the urinary bladder of a

rabbit previously prepared for an experiment and made an observation on the

effect of bile juice and pH for the behabiour of the fluke. The result showed

that the majority of flukes proceeded to the ureter with the bile juice (pH 7.4-7.6)

5 hours later. But when sodium carbonate was added to the saline walel'

(changing pH to 7.8-8.0) many youn[! flukes pos山 velyproceeding into medium

were observed. From these γ'esults YOSHIDA concJuded that the hydrogen ion

concentration had an impor回 nteffect on the invasion of the fluke， provided

that pH was under 9.0

Regarding the distribution of flukes in the liver， lTO et al. (1925) autopsied

21 infected rabbits and examined Clonorclus adu¥ts. The result showed that the

highest incidence was observed in the right lobe. When dividing the liver into

the anterior and posterior part， the higher percentage of flukes were found in

the anterior one. In the case of dividing the liver into the central and

peripherial parts， the majority of ClonorchIs adults was found in the latter. On

the other hand he found a large number of fl.ukes in the central part of the

liver after the death of the host. The reason could be explained as follows;

After the death of the host， the temperature in the peripheral part would fall

Quicker than that in the central 0

58'

0.6 % salinc solution plus bile juice)， became more actIve when CO， was introduced into it. He assumed that the activity of伺ukeshad a closc relationship

with carbon deoxide in its mediu m

C. Development o( F¥uke in Definitive Host

1. Growth of the worm in the definitive host

KOsAYASHl 0912a， 1922) fed guinca pigs with Clonorchis metacercariae and

observed tl1at thc fiukcs became smaller in size when they hal'boured more in

number. On the growth of f1ukes in the guinea pigs. hc obtained thc results

shown as in Tahle 6. In rats young worm grew as equalJy as those in guinea-pigs

within one week， but after that the growth of the fluke in ra阻 wasremarkably

retarded as comparcd with that in guinea pigs

KOsAYAS川(1912a)ob田 rvedthat the acetabu!um of the伺ukeexceeded the oral

sucker in sIze up to the fourth day after fecding. From the fiflh to lhe seventh

day the加thwere cqual in size and from the lenth day on the oral sucker

became larger than the acetabu¥um. ln the metacercaria¥ stage of the伺uke

numerous concretions and granu¥es were observed in its excrelory vcsicle. but

日 veralhours after cntering the final host出eyal1 were found disappcared

Table 6. Growth of young CIOllorcflis w川、inthe guinea pig lK08AYASIII. 1912a， 1922)

~ 2_3_._._'_w_w_m_u_ length 0.27- 。.3 0.5- 0.57- 1.1- 1. 5- 3.2 ι5 ι.-

0.36IOm. 0.4mm. 0.61010. 0.72mm.1.2mm. 2‘Omm. 4.0mm. 5.0mm咽 7.5mm.

breadth 0.0SSO，O710.1- 014- OE- 0。3- O，54- 1+01 .5-0.081mm.0.1mm. 0.12mm. 0.161010. 0.26mm. 0.4mm. 0.6mm. 1.2mlll. 2.0mm.

According to KOBAYASHI (1922)， the development of thc genital organs of

CIOllorcllis sillcnsis after invading the白nalhost is as follows. On the白fthday

after illvading the final host， both the testes begain to田 ndout lobes. 011 the

seventh day their lobulatcd form became as conspicuous as is seen in the adult

The ovary took its characteristic lobated form aftCI 自vedays. setween the

seventh and tenth day a smal1 sac appeared on the posterior right side of the

ovary. The sac became a時間nalvesicle later. The uterus in the larval stage

was straight duct connecting the ovary and th巴 genitalopening. With the

developme川 ofi1S r泥沼hboringregi聞 は elongatedand on the日 venLhday its

lateral loops cou¥d be ob田 CV国 The egg formation began between the twelfth

and fifteenth day; during出isperiod the outline of testes and ovary becamc

more compact. The vitellaria could be hardly recognizible until the sixtee川h

day. setween the twentieth and twenty-third day lhe uterus was filled with

eggs. On the twenty-sixth day the eggs could be recovered in the feces of the

host

'88

2. Devε]opment of excretory system

011 the deve]opment of the excretory system of C. sinellsis in its definitive

host. a detailed description by KOl¥HYA et (11. (1953) is available

They fed tnice with metacercariae and aIler a certain period of time they

¥¥'ere dissecled and examined the development of excretory system in every

developmental stage of the伺uk，The data obtained are as foJ]ows

One day after infection: The warrn was already in the liver. In most

cases， neither excretory corpuscles nor granules were found already In the

excretory vesicle. The flame part of the ftame cell ¥Vas 8. Iμlong. The main

excretory canal became considerably larger in diameter. The伺amecell formula

remained as the same as that of the cet'caria and metacel'caria: 2x [(3+3)+(3

+3+3)1

Two days after infection: The body of the worm was 0.56 mm. long and

0.15 111m. wide. The main exc陀 tol'ycanal became larger， measuring 5.4μm

its diameter. The flame cell formula remained as the same as before

Three days after infection: The body of the worm became 0.73 mm. long

and O. 19 mm. wide. The flame cell formula remained st川 asthe same as before

Four days after infection: The body of the worm became 0.91 mm. long

and 0.24 mm. wide. The flame part of the flame cell wasεnlarged to 9x4.5μ

and the diameter of the mail1 excl'etory canal measured 7.2μ ln this stage，

the flame cell formula stiU remained unchanged as before

Ten days after infection: The body of the worm became 1.4 mm. long and

0.28 mm. wide. The both suckers were still of the same size. The flame cells

川 thepos句riorsecondary collecting tube remained unchanged in number and

arrangement. but a new small flame ce¥l was seen on the foremost original one

of both first and second tertiary excretory tubes of the anterior secondary

collecting tube (Fig. 8， a). Sometimes， such a feature was found only in the

first tertiary collecting tube. The new flame cell was about 12 in its size of

the original flame cell; the flame part of the latter measured 9 x 4. 5μTh， flame cell formula in this stage was principally 2x 1(4+4)+(3+3+3)]

Twelve days after infection: The bOdy of the worm became conspicuously

larger. measuring 2.9 mm. long and 0.45 mm. wide. Particularly， the posterior

part of the body was found markedly elongated: it was about th問 etlmes

as long as the anterior part of the body. In this stage， the flame cells in each

tertiary collecting tube increased cOllsiderably in nurr】ber. Each of the three

original flame cells of the first tertiary collecting tube was added with 3 to 4

new flame cells which were usually smaller in size， about 1 2 of

Fig. 7. The excrelOry systen、。fClollor(hi$ sillr"sis in cercaria and metacercaria stage. lKo .¥IIYA tl 01.， 19531

a: m cercar‘a b: in metacercaria

日-

:'1¥0'

•

Fig.8. TI時 excrεtorysystem of C/Ollord，;s sim!nsi5 in its definitive host. (KOMIYA el al 1953) a: ten days after infecti加

b: Iwelve days after infection c: twenty four days after infection. d: Ibi(f

""

rhc newly added flame cells were found grouped around the original one. On the

second lCl'tiary collecting tube， two anterior original Aame cells werc added with

Ilo5ncw 伺amecel1s respcctively， while the most posterior original onc 7 to

a new f1ame cells. These new flame cells wcre about the same as those on lhe

first tertiary collecting tu困 insize and arrangement

Each original flame cell of the third阻"叩ycollecting tube was added with

2 to 5 new何amecells. The Increase of ftame cells in the fourth tertiary collecting

tube was the same as that of the third one， whi1e each original ftame cell of

the fifth tertiary collecting tube was added with 2 to 4 l1ew ftame cells

respectively. Fig. 8， b re叩 resentsan example of the l1umber and arrangement

of the flame cells in the worm in this slage. Here， the ftame cell formula 011

刷 leside was represented as ¥(4+4+ 5)+(6+5+9)1 + [(3+6+3)+(3+3+5) +(3+6+5)j

Fifteen days after infection: The general as回目 of th巴 increase and

arrangt"ment of the伺amecells was almost the same as those twelve days aftel

川 fCC1IOll. Each original ftame cell in the metacercaria stagc was found increased

by 3 to 9 in IlUmbel.. The number of the flame cclIs on each tertiary collecting

tube was not always constant

Twenty four days after infectioll: The body of the worm was 5.5 mm. long

590

3nd L 7 mm. wide. The diameler of the main excretory canal attained to 7.5μ

Bllt the flame part of the flame ccJl was oot so large as compared with that

ten to twelve days after infectioo. The largest size of the flame part of the

伺amecell remained 9x4.5μas yet. The size of the flame cell田 emedto show no

fllrther increase. ln this slage the number of the flame cells was found

considerably increased， bul it was very difficllll to elucidate the exact feature

of the number and arrangemenl of伺amecells 011 every tertiary col!ecting tllbe.

p31.ticularly on that locating in the middle parl of the body， because here the

extensive development of the uterus became an obstacle to the exact observation

With great effort. KOM!YA et al. were able to make clear the aspect of the numbel

and arrangement of the flame cells 00 the first， second and fifth tertiary collecting

tubes. Fig. 7 and 8 show an example of the arrangement of flame cells 01 this

stage. As seen in the Figures. each of the original three flame cells on the first

tertiary collecting tube increased by 6 to 14 in number respectively， and those

of the second and third ones by 10 to 14 in number rcspectively

From the observations mentioned above， KOM!YA el al. (1953) stated that no

de自oitefactor of division or no regularity in division of flame cells was rccognized

in the COUl配 ofthe iocrease of flame cells in young Clonorchis in its final host

3. Longevity of the C. sinensis in the definitive host

KATSURADA (1916) cited a case of clonorchiasis which was believed to have

harboured an infection for 3 years and 11 months. KOBAYASH! (1922) took the

melacercariae himself in 1910， and hc noticed eggs in his feces one month latcl

ln 1919， he found a marked decrease in egg number in fcces and concluded that

the 1ife span of Clonorchis in human bodies may possibly be wider than 8 years.

On the 3 dogs experimentally infected with the fluke， MUTO (1922) noted the

decrease of egg number in feces 2 years and 8 month$， 3 years and 4 month$

<lnd 3 years and 6 months after infection. On their autopsy， he observed

degenerated atrophy of the fluke from them

In this regard， MUTO considered that， in the fluke， with the atrophy of the

body the gradual degenerating changes of the reproductive organs were occurred

<lnd subsequently the reduction of the egg number in the uterus took place

until they eventually died

'1. 1n vilro cuJture

fo this point no 1'eports、.¥'ereavailable recently. In εarly times SH!I¥1AZONO

e/ al. (1916) cultured young worms (5 hours 01' 11 days after infection) in variou

591

a cloth plus 9 volumes of 0.6.9百 sterilizedsaline solution)， was most efficient i11

maintaining their survival (6-37 days)

REFERENCES

1. ANDO， A. & K. KOBORI (1924): On an abnormal modc of infection of CIO!lorchis SilICIW~

1. Oral infe<:tion and thc relation between C. sIllclIsis and birds. Cflllg削 ljiShiJ/to

(1057)， 523-535. (in japanese) 2. ARJYOSHI， C. (1930a); A study of the liver of the rabl川 experimentally infected with

CIQ!wrcllis si川町Î.~. sJorぽ刊/1 Ki)'o， 6 (2)，277-362. (in Japanese with English summary)

3. ARIYOSHl， C. (l930b): The infestation of thc pancreas with CIQ//Qr，ιfus sillclIsis 3nd

its histological study. Byorigak/l Kり0，6(2)， 363-372. (in japanese with En兄lish凹 mmaryl

'1. ASADA， J. (19四 ): Study on trematodes in birds. Nitf/O!I 8yori G叫加iZasshi. 1日 347

350. (in Japanese)

5. ASAQA. J. (1937): Study on trematodes in Manchuria the intermediate hosts of which

are fresh water fishes. particularly recovered frorn dog experirnentally. Ni，仲 011KiseIl:11II

Gakkni Kiji， 9， 103-108. (in japanese)

6. ASAOA. J. (1940): Clonorchias凶 in M主nchuria. 1. Particularly On the prevalence of

clonorchia引 sin Mukden. ，/，(iirikll Kngakllill 1110. 4 (6)， 932-956. (in japanese)

7. ASAOA， j. (1942): 00 pHasites， particularly on helminths in Manchuria. NゆpOl/!US('ir"i1ll

Gllkkai KIji. 14， 22-44. (in ja凹"'溜)

8. BAELZ.巴 (1883): Uber einige neue Parasiten des 1¥1enschen. 8erl. Klin. Wochenschr

1883， 23.1 238

!). sLANCHARD， R. (1891): Notes sur quelque渇 versparasites de I"homme. Dislolllfl SiIlCIIS.

Comtl， rClld. $0'. biof.， p. 604

10. BLAトαIARD. R. (1895): 0ρ stllorcflis sil1clIsis. "in Traite de zoologie m剖 icale et

argricole" 2d ed.， Paris 11. BLANCltARD， R. (1896): Parasites animaux. Jn Traite de pathologie generale. Bonchard

Paris. 2，“9-810 12. Braun， M. (1920): Die Tierischen Parasiten des Menschen 11 teiL Wiirzburg

13. CIIOW. L. P. (1960): Epidemiological studies of clonorchiasis at meinung township in

southern Taiwan. FOI'IIIOSOJ/ Sci.， 14 (3)， 134-166 14. CHUN. S. K. (1962): Studies on some trematodes whose intermediate hosts are fishes in

the Naktong River. 8111f. Fishe，.ics Colll!gc. P/lS叩 Nol.Ullill.. 4 (1， 2)， 21-38. (in Korean

with English summary)

15. CUUNG，日 L.， S. j. HUANG， T. H. LI， H.C. Hsu， Y. M. Hu & F. N. Hsu (1959): Studies

。nclonorchia引 ssinensis in Peking and Tientsin. Occurrence of clonorchiasis sinensis at Yungfeng Hsiang. L山 lit'unof Ch'angp'iog district， Peking， with observations on

intermediary and definitive hosts and detectωn of clinical cases by means of intradermal

test with CI0I10Tc/lis antigen. ScieJ/cc Rccon/， New Ser.， J (10)，49ゅーる03

16， CUUNG， H. L. T. C. I-Iou， S. J. HUANG， P. S. 1¥10， L. Y. Ho & C. H. KUANG (1960): Stud悶

on clonorchiasis sinensis i:J Pi:!dng and Tientsin. Occurrence of clonorchiasis sinensis

in Peking and its suburbs， wI!h observations on secondary intermediary and definitive

hosts. Ibid.， 4 (1)， 19-25 17. CHUNG， H. L.. T. C. I-Iou. H. C. Hsu， P. S. MO & H. C. WENG (1960) : Studies on clonorchiasis

sinensis in Peking and Tientsin. Occurrence of clonorchiasis sinensis at Palit'al， Tientsin， with observations on intrermediary and de自nitivehosts， Ibid.. 4 (1)， 26-32

18. COBBOLD， T. S. {1815 a}: The new human fluke. Lnllcel， 187も (2)，423

19. COBBOLD， T. S. {l815 b}: The new ¥iver tluke. Vele，.illarioll (London)， 46， 780-781

10. U)BsOLD， T. S. (18日S4): Flukes in man. LlIII'el， 1884 (2)， 976

21. EGUCHI， S. {I925}: ]>arasiles of wild animals， parlicu1ar1y lhose of fierce animals and

the inte問 lationthose human parasites. Aichi Igak如 iZaS$lzi， 32 (6)， 176-189. (in ja四 nese)

22. FAUST， E. C. (1925): Somc recenl as凹ctsof the叩 demiologyof Clol1o/"cllis infection in

592

China， CIIiIU/ MI'II. J.， 39 (4)， 287 -295

23. FAUST， E. C. & Q. K. KIIAW (1927); 5IUd附加 C!flllorrliissiIlCIIU，' (Co帥 01.0. .-¥:11. J Hyg.， MonogげaphicSeries， No. 8. 284 pp

24. Hi¥SEG.¥WA， T. (1929): A morphological characteristic of CIυIlfIrdus egg. An ilrabesque

p)lygonユ1pattern on the surface of tl憎 shcll. Ok(IJ"l1川 fI Ij.fflklmi Zfls.IIJi. 41 (101， 2424

(in 1apanese)

25. HA$EGAWA. T. (1934): Uber die enzystienen Zerkarien in P~clldornsboJ"(l 何町'(1. lbid.，ω (6)， 1397-1434. (in japanese with German summary)

26. HASU[， N. (1917a): Biological study on Clollorrllis sillclIsis. Ibid.， (325)， 33-40. (in Japanesel

27. HAYASII[， 5.， K. 5ATO， M. 5mGA & K. YAMAOKA (19喝7):The area along Lake Suwa

area. Nagano Prefecture as an endermic area of C/flllordlis siJ/cllsIs. KISl'ICJlIIgflkll ZflS$l1l

6 (3， 4)， 361. (in japanese) 28. HIGU乙11[，R. (1938): A contribution on tl惜 morphology of Clol/on';'is 5Illrllsis in

Para[()s目7ntlusIIwllchQlllic"S， Kcio Igllkll， 18 (12)， 1289-1305. (in japanese with English

summ同y)29. HOR1GUCIII， T. (1941): The effects of Vitamin C upon the development of CIOIIOl"clli，<

Silll:llsIS in the final hos1. Nゅρ0111 ka Daigukll Z，ω叫ん 13(12)， 952-953. (in 1a凹 nesel

30. HOR1UCIIl， K. (1956): Epidemiological studies on c 。、orchiasisin Noshiro are<l， Akita Prefecture. Akilakell NosolI Igak如 iZa$$hi， 3 (2)， 32 68. (in Japanese)

31. HOZUMI， K. (1925); On donorchiasis in Niigata Prefecture and on Melagol/imus J'okoga川 Mand larval form of Ligllla formed DipJt)"/{oゆolltl"illll/. Nip，仰 115110村知byoGak加 i7.asshi

24 (4)， 254-266. (in Ja凹 nese)

32. Hsu， H. F. (1939); 5tudies on certain problems of CIQJ/on;his si>lc叫 isV[]J. Further

advance in the study of the life cyde of CIOl/orrflIs silwlIsis. Chillese Metl. J.. 55. 542

545 33. HsU， H. F. & C. y， CIIOW (1937): Studies on certaln problems of C/ol/ol'chis sil/rllsis 11

Investigation in the chief endemic center of China， the CanlQn area. Cltillese Mr(l. J 51，341-156

3，1. Hsu， H. F. & C. Y. CIIOW (1939): Development of CloJ/orc/lIs si/Jellsis eggs 10 cercaria

民agein laboratory bred snails， silh)"l，;a [uchsiall(/. Pr，ω 50c. E.ゅ Bio/.Mrd.， 41. 158

160 35. Hsu， H. F. & O. K. KIIAW (1936); Studies on certain problems of Clollo/"chis sil/ellsis 1

On lhe cysls and second intermediate h田旬。fClollorr.ltis sil!ellsis in the Peiping area

Chi'le/Jse Med. J.， 50， 16心9-162036. Hsu， H， F. & O. K. KIIAW (1937): Studies on certain problems of CIOIIQ/"eltis Silll'>lSIS 111

On the morがIOlogyof the metacercaria. Feslsrll川 flBl'rllllflrfl NOrlll， HOII山 11"1{， 216-220

37， Hsu， H. F. & S. Y. LI (1940): Studies on certain problems of CIQII(}I"';';$ silll'lIsis. 1X

The migration route of its early larval stages in the snail， silhJ'llIa [lIrll針。1/(/. Cflilll'sl'

l¥IIed. J.， Suppl.， 3， 244-254

38. Hsu， H. F. & L. S. WANG (1938): Studies 0

593

(470)， 253-256. (in Japane氾叫43. !!JJMA， L (1886): Dislo川 aflldemicuJII， BAHLZ. J. Colf. Sci. Imt. UllilJ. TokYQ， 1. 47

59 “hJIMA. 1. (1888): The aoimal para叫 esof man. .190 pp. Tokyo. (in Japanese)

45. lKUYAMA， T. (1960): Studies on CIQIIQrcllis sillclIsis in the lower basin of the River

Chikugo J. Results of the survey on cJono閃 h・asisin Saga Pref.田ture. I¥rI/"IIlIIf! IgaA'A'ai

Zasshi， 23 (7)， 2730-2753. (in Japanese with English summary)

46. IKUVAMA. T. (1960b): Studies 00 Cfollorchis Sillf!II$IS in the lower basin of the River

Chikugo 11. Results of the surv町 onclonorch・"・sin Fukuoka Prefecture. Jbid.. 23 (7).

2754-2776. (in ]apanese with English sumrnary)

47. INAG .~削 M. (1952): The prevalence of Clollorcltis metacercaria during 1951_1952. ][

Investigatio田 00the incidence in Tokyo and Ibaragi Prefecture. Ni.ρ仰 uKisci叫 11 Cakklli

Kiji， 21， 62-63. (in japanes叫48. INATOMI， S. (1953a): Studies on trematodes in Okayama Prefecture. 1. The development

。fPara!ossarllfllS 1II11IIc/lOlIriCIIS and water Quality. Okll)"alllll 19l1kんaiZa.ulti， 65(1)， 31

39. (in japanese)

49. INAT.)MI， S. (1953b): Studies on tremato:les in Okayama PrefeC¥ure. IV， The seasonal

、lariatぬnof the cercaria in Parafo.崎市1r1l!IISmauchOllriws snail. Ibu!.， 65 (1)， 43-45. (in japanese)

50. INATOMI， S. (1953c): Studies on trematoヨesin Okayama Prefeclure. V. The distribution

of ParafossarlllllS m(lI/cI!OIlJ'iCIIS in the coast of the Kojima Bay. Ibul.， 65 (1)， 45-49. (in japanese)

51. ISHlI， S. (I929a): Studies on clonorchiasis in Kwangtung. 11. On the Clol/oJ"cllIs egg in

feces. jikkclI 19akll Zasshi， 12 (2)， 39-59， (in Japanese)

52. ISHII， S. (1929b): Studies on clonorchiasis in Kwangtung. IV. On the second intermediate

host of CIOl/Orchis sincIIsit. /bid.， 13問。 111-183.(in japanese)

53. ISIIII. S. & F. MATSUOKA (1935). Study on the relationship betwccn ClonoYl:hi.. infcctioll

and water. Tok)"o lji SflInslti， (2912)， 80-回(inJapanese)

54. ISHIZAKA， K. (1818): On the results of凹stmortemexamination of liver trouble disease

and its clinica! symptoms. Igllkll Z，“5slli. (40)， 20-26. (in japanese)

55. ISODA， M. (19日 ): Experimenta! studies on clonorchiasis 1. On the distribution of

metacercarb in the body of PJCII/lorasbora t{/r叩 and experiments on the artifidal

infection with metacercll.ria in rabbits. Nゆ仰11 jlligakll ZlIsshi， 14 (2)， 105-114. (in

japanese w・thEnglish summary) 56. ITO. K. (1926): Bblogical studies on the cercaria of Clollorr:!，;s sine出 is. Aichi IgfiNNai

Zassfl人 33(2)， 389-402. (In Japanese)

57. ITv， K. & M. MUTO (1925): The dislribulions of the worm in rabbil!l of the exper・mental

donorchiasis. 8J吻rigakll 1<i)'o， 15，565-571; Aichi Ig/lkklli lf/S♂lii， 32 (6)， 1013-1081. (in

Japanese)

58. lwATA， S. (1937): Experi

594

par1'_sito!ogical z回 logy.Nissltill fgaklt， 1 (3)， I ~ IO. (in Japanese)

64. KAWAI， T. (1937): Study on animal on anthelmintic effect of gentian violet. Suppl

The evalualIon of WAK~;SHJMA '5 egg counting method as an assay technic of anthelmintic

eITect of drugs against CloIIOI'，IIi$ sinClIsis. TII;W(II/ Igakkoi Zasshi， 36 (5). 927-934

(in Ja凹 nesewith English summary)

65. KAWAI， T. & Y. YUMOTO (1935): 00 the distribution of the encysted metacercariae of

C/oJlol'chis siJlellsis in P;;emIQI"osbQI'(Iρan'o as the鑓 condintermediate host. and the r3te

of their infections to the marnmalian hosts. Jbid.. 35 (4)， 880-887. (in Japanese wilh EngJish summary)

66. KAWANA. H. (1936): 5tudy on CIOJ1Qrchis sinclIsIs in the district of Shanghai. 111. Dogs

cats and ralS as reservoir hosts of C10lIorchis. J. SfwlIghai Sci. Il/sl.， l$ect. 4). 2. 75-

" 67. K1M， J. W. (1961): ClOllorchis si阿川崎川 varioussecond intermediate hosts and th創 r

seasonal variations in Dog.chon area of the River Kumho. Ncw IIIcd. J.. 4 (10)， 1221-

1223. (in Korcan wilh English summary)

68. K1TAMURA， K. (1916): An unknown helminthic eggs found in man. JikkcII 1110， 2 (16)。{in Jap:mese}

69. KOsAYAS1I1， H. (191011.): A study of liver distoma. The first preliminary report

DobllfslIgakll Zassfli， 22 (264)， 1-4. (in Japane副

70. KOIlAYASHJ， H. (l910b): A study of liver distoma (Preliminary陀凹rt). SaikiJlg(lkll

/σsshi， (178). 49-51; (180)， 1-6. {in Japane則

71. KOIlA YASIt1， H. (191Ia): A preliminary re回目 on the source of the human liver distome

CJonorchis elldemicus (BALZ) (-D;SIO/ll1l川 sρ71fwlalllll1 LEUCKART). Allllol. Zool. Jap

1. 271-277 72. KOsAYASH1， H. 0911b): A study of liverdistoma出 condaryre凹 rt).SlIikillgakll ZassfII

(185)， 1 2. (in Japanese)

73. KOsAYAS1H. H. (l911c): First intermediate host of CIOIIQrchis. Ibid.， (188). 1-4. (in

Japanese)

74. KOBAYASH1， H. (1912a): A study of CIOlIorcllis SIlltilsis (Final re凹 rt). Ibid.， (20). 1-66

(in Japanese) 15. KOsAYAS1H 日 (l912b):00 the life h凶 toryand morphology of the liver distome(Clollo，.c/tis

SiIlCtlSis). Cetllmlbl. B叫 1.Pamsil. 01'ぽ 75(4). 299-318.

76. KOsAYASIt1， H. (1915): Studies on the enaoparasitic trematodes. D，ωIIlslIgaku Zasshi. 21

(320)， 1-13. (in Japanese) 77. KO也AYASIII，H. (1917): On the 1ife history and morpho1ogy of the liver distome (CIOIIOrChIS

S/Jwns叫 Mμleil.Mcdiz. Hodtscflllle ut Keljo， 1， 251-284

78. KOsAYAStlT， H. (1922): The由。logicalas開ctsof c1onorchiasis. Nisshill Ig(lkll， Suppl.，

1-56. (in Japanese) 79. KOsAYASIlt， H. (1923): On clonorchiasis in China. CItOSCII Igakkaiノ'assh人 42，80-87. (in

h問 n目的

80. KOsA YASHI， H. (1924a): On the human I1ver fluke in Korea and a note on the intermediate hosts of the liver lluke in China. Millcif. Mcdiz. Hocllscfmle ZII J(cijo

595

{21. Especially the relation between C. SUlc.，sis and COz. Ibld.. 34 (10)， 1513-1525. (in 片岡田健}

86. KOOA. 1. (19陪2):On human parasites in Kumamoto Pref.民 ture.esp舵 iallyon t問 matodesNittoll B)'ori Gfl帥 fliKfliho， 12， 120-149. (in japanese)

87. KOOA. T. (1936): On the study technic of the distribution of ClOl/Orcltis SillC11悶

SntklllgflN/I Zflsshi. (479)， 15-21. (in japanese)

88. KOMIYA， Y. (1955): CIOIIOI叫 IssillcII$Is. - The endemic disease in japan ShIZcJ/

1日間， 2&-33. (in Japanese)

89. KOMIYA， Y. (1961): The excretory syslem of digenetic trematocles， its deveJopment and

relation 10 laxonomy. K信仰dlllgakll Zasshi， I日(3)，369-378. (in Japanese with EngJish

lIummary)

90. KOMIYA， Y. & H. KAWANA (1935): Study on Clollorcflis sinc/lsis in the dislricl of

Shanghai 111. Dogs， ca匂 andralS踊 thede1initive host of CfOllorchis引川町is.S加 "g加，

5111uII Kagtlkll Ke"kyujo 1110， 5 (9)， 59-70. (in Japane鍵}

91. KOMJYA， Y. & H. KAWANA (19361: Study on Cf01lorchis SillClI$IS in the district of Shanghai

IV. The 館四nd intermediate host of CI削 orchisSIIICIISis. Ibid.. 5 (l4)， 205-217. (in

Japane鎗):J. SIwIIglwi Sci. IIISI.， (Sect. 4)， 2. 155-167 92. KOMJYA， Y. & S. KONOO (1949): Am1S domcslica as a definitive host and OpllicepJ/flllls

tlrgus回 a 町田町d intermediate host of CI側 orcll;ssi川町is. Seiltli 110 Kagoku， 1 (1)，

31 33. (in ]apanese); Joρ Med. j.， 4問 .157-161. (1951)

93. KOMIYA. Y. & T. KAWANA.TAJIMI (1953): The development of the ex(;retory s)'Stem of c/.岬 rcJ/lSs;lIellsis in its de自nitivehost. Jaρ J. Med. Sci. & 8;01.. 6 (6)， 571-575

94. KO~IIYA. Y. &K. MURASE(l944): Onthedistributionof various metacercariae from the

1ish body. S加 ngJwiSIIiu!II Ktlgakll Kellk)'ujo 11/0， 14 (6)， 4'9-434. (in Ja回目鍵}

95. KOMIYA. Y. & K. MURASE(l951): E侃(;a(;yof digestion method for collecling metatercariae

from the fish以xly. Jaρ Med. J.， 4 (1)。拍-<8

96. KOMtYA. Y. & K. MURASE (1952): On the distribution of variou8 metacercariae of

trematodes within the fish body. Jaρ j. Med. Sci. 8iol.， 5 (5). 277・29也

97. KOMIYA， Y.. N.SUZUKI， M. KUMADA， T. FUKUSHIMA & 1. KOZAI (19唱。);On the distribu tion of C. SIlle"sIs around Lake Biwa areas， Shiga Preh淀川re. KIsucllugakll Zasslli， 9

(2). 162・166.(in japanese with English summary)

98. KOMIYA， Y.. N. SUZUKI， M. KUMADA. M.SIIlGA & E. OBI (1957): On the prevalen目。f

c/.岬 rchisumwsis in the districl of Lake Suwa， Naga叫 Prefccture. NitρOJI KOlls11It

Eisci Zasslti. 4 (4). 200-202. (in ]a岡田.，)

99. KOMIYA. Y.， H. TAKANO & Y. OGURA (1950): Studies on CIOlIortllis simwsis in Oura

diSlrict. Gunma prefecLUre. KOlIshll Eisei， 8 川 198-199.(in japane削l曲 KO~IIYA. Y. & Y. T叫 IMI(1942): Fresh water fishes as the関田ndintermediate h曲，，'

trematocles in Central China. NiptoJ/ KiseIcll/l G(lk加 ;K明 14. 87一関 (in ja田 nese)

101. KO~HYA ， Y.&Y.TAJ IMI (1 940 ) : SLU

59o

106. LF.UCKART， H. (1876): Oie menschlichen Parasiten. sd. 11.， Leipzig u. H削除lberg田2pp

107. LWCKART， R. (1889): Oie Parasiten des Menschen 11. Au伺 2Abt.， Leipzig u. Heidelberg

440 pp 108. Looss. A. (1907): On some parasites in the museum of the School of 1'ropical Medicine，

Lh'erpooJ. AIIII. 1'rop. Ml!d. Parasil.. 1， 123-152

109. MCCONNI::I. (1875): Rernarks on the anatomical and pathologica 1 relations of a new spec陪 S。fliver fluke. Lancel， 1875 (2); 271-274

110. MIKI， T. (1922): The 民 :cond intermediate host of Clonorcf山 silll!lIsisand i凶 relation

"山 cercaria. .Niptoll Byori Gak加 ishi，12， 116-118. (in japanese) 111. MI¥'ANAGA. S. (1939): The second intermediate host of Clol1orchis slllcl1sis in Mukden

and its vicinity. Mtll/slm Igakll Z.仔sshi.31 (3)，565-568. (in Japanese with English summary)

112. MIYOSHI， H. (19~8) : Studies on the encysted metacercariae wh釦ck takes fresh water

fishes as their second intermediate host in Katayama d凶trict. 50go Igakll， 5 (11)， 474 476. {in japanesel

113. MORIS!l!TA， K. (1951): The paras川icdisea鍵 sin Japan. 5引 shinKiseicflllbyogaku， L 96

pp. Igaku Shoin， Tokyo. (In japanese) 114. Mo恥"制TA，K. (1954): The study on Clollo/"chis sillclI5Is in Japan. 1'ok.¥"o lji 5f1i1lSIIl，

71 (6)， 343-347. (in lapanese)

115. MORISI¥lTA， K. (1959): The post-mortem examination of Mr. A. SUZUKI. A page of the

history of the study on C 刊 /ClIsisin la問 n. Niptoll Iji 511ill向 (1811)，79-83. (in Japane明 }

116. MUKOYAMA. T. (1921): The experiment on the route migration of the larva of C. Sinl!lISis

in the final host. NiP.向 118yori Gak加 ishi，11， 443-445; Aichi 19ak加 iZasshi， 29 (札88-103. (l922) (in Japanese with German summary)

117. MURAKAMr. S. (1937): The egg shell formation of trematodes. Okayama Igaklmi Zasslt人

49 (4)， 705-768. (in Japanese)

118. MURAMATSU， K. (1927): On the distribution of fat in the worm body of human helminths

Hoklll!lSIf 19akkai Zasslli， 42 (5)， 531→553. (・nJapanese)

119. MURASE， K. (19巧0):Studies on trematodes凹 rasiticin fresh water fishes as the second

intermediate host in Kaibe-gun， Aichi Prefecture. Aiclli-kl!lI Eisei Keulり，リ'0Hokokll. 2

15-17. (in Japanese)

120. MUTO， M. (l917): Studies on heJminths whose intermediate h田 tsare fresh water fishes

from Lake副wa，especial1y on jr4elllgollimlls yokogall'ai whose intermediate hosts are

Cyprill川町rpioand Carassi目印rassills. SflOkt1kibyogak/f Zflsshi， 16 間 135-166. (in

Japanese)

121. MUTO， M. (l918): On the first intermediate host of ClolI()l"chis SIII♂IIsis. {First report)

Ni仲0118yori G付加ishi， B. 22渇 230.(in lapanese)

122. MUTO， M. (l919a): On the first intermed剛 ehost of ClonorchIS sillellsis (Second rep。川

Cfl/lQ Igllku Z(lsshi， 26 (3)， 1-28. (in Japanese)

123. MUTO， M， (l919b): Experimental stud同swhether Clollol"chis silll!llsis can be infected

through water and the significance of its 民団ndintermediate host. lji 511illρ。{10251769-788. (in japanese)

124. MUTO， M. (i919c): On the infection r

(in Japanesel

127. MUTO， M. (1921): Experiments on the filtration of water containing encysted larvae of Clollorchis sIllclIsis. Niptoll 110 Ikai， 1 (1)， 8-10. {in japanesel

128. MUTO， M. (1922): Duration of life of ClollorcflIs sillclIsis in the body of the mammalian host. 1"0勾o/ji SfliIlShi， (2292)， 1656-1660. (in Japanese)

129. MUTO， l¥'1. & K. KODAMA (1918): Stud四加 theroute of infection of Clollorcftis sillcJlsIs

59;

11. Can the回 rpand the gold fish serve as Ihe SE回 nd;ntcrmediate hO$11l of Clollorrllu ? Iji $11111111111， (10261制8-858.{in Ja田町鑓}

130. MUTO， S. {l9381: 011 ClllluirltlllS Imcri (KREYENBERG)抽 the縛 cond inlermec!聞.h曲【

。fClo!/l}l'(/lIs SIIIt!IIS1s in Formosa. 1"11111"(11/ Ig(/H"(/I Z(/SSIIl， 31 (10)， 1537-1539

131. NAGAMOTO. K. (1959): Studies 011 clonorchia!lIs 1. A sur¥'cy of乙'/ollorc!ti，s 5111/111S13 in

the basin or the River Onga. !UtrIIlIlC IKflklulI 7.IIH/II. 22 (41， 13制 1398.(in Japanese wIth l~ngl Î sh summary)

JJ2. NAGANO. K. (19271: The geographical rlistribuい011of the fil'st intermediate host. 81111)'1川

.<1";(/111111 var. ja仰Jlifa.in O:.cayama PrefeclU問 ο加 1'11山 '1IKflkkll1 7.1I$shl. {44'1I， 124 132 {in Jap11llωe with Engli!lh summa円YI

1:1:1. NACANO. K. (19281: Studies 011 the eradic担lionof c.:. ullclI..is 1. The tecJ川トcof the

eradication of由民rst1I11erm同協同 h師 1，!J1/l1)'11If1 #1'川 t巾 bymean!l of removing、yaterweed and by inserting bamboo into waler. '/υkyo Ijl Shlllslt;. (2563). 557 558. (in Japanese

l訓 NAGANO， K. (1950: Pre¥'ent;on and therapy of donor出削凶恥川111 Ki.wi(/lIIb)'ogflkn

1V. 43pp. Igaku 5hoin. Tokyo. (in Japallese)

135， NAKAYAMA. H. (19101: The developmem of the cgg of Cltmρ/，(/11.( .'1/IICIUI.". 7'okJ'o Igρ"仰，

7.lIsslll. 24 (12)， 1-51. lin Ja凹 nese)

1:16. NAKAYAMA， K. 11912): The structure of the vilelline gland訓nrluterus of l'lIrngOIllIllIl.<

and Cfol/orrll/S. Ibid" 26 (2)， 1 13; (31. 18 65; (4). 10 48. (in Ja岡"'鍵}

日7. NISIUMOTO， M. (19581: 5todies on Clollor('llI.c sil/f'l/sis in Tokushima I'refecture. particularly

.h.行rstintermediate h田t. Sltikokll Igllkl/ Zlm;!，;. 12 0). 580-595. (in Japanese with

ト~ngli曲!iiUlllmary

138. NJSHIMUIIA. 5. (1938): Human intestinaJ parasiles In Kyung sang Puk 00， Korea. Tnikylt IglJklt S~IJIIIQI/ G岬加 Zns.shi.4 (1). 40 50. (in Ja問問剖

139. OKAB区 K.(1937): On the町 currellcesof cJonorchiasIs in Yanagawa district， Fukuoka Prefecwre 升Itkml加 Ikn /)a;gnklf ZflS5lti， 30川 151 155 川 Japane田 with Eng1ish sumlllary)

140. OKABE. K. (1938a): On 1'lIm/03Sf/rl/{l/.c IIl1l11rJwlI，.;nls in Fukuoka Prefecwre. ¥'1'11115. 8

(2)， 97 102. (In Japanesel

141. OKAs払 K.(l938b): 00 the second intermediate hosts of Clllllo/，('ltis 511/1'11315 (COB箇0'"in Fukuoka Prefecture. Fukllo加 Jkll Dω'gllkll 7.11ω111. 31 (7)， 1217 1229. (in Japanese

with English summary)

1'12. OKAsR， K. (1939a): The 1削 ofmelace陀 ariaein fish h曲凶 inNOl'lh Manchuria. Fllkl/oHtI

Jgllkll 7.•ω $$111. 32 12). 289 296. (in Japanese)

1.13. OKAsE. K. (1939b): Observation 011 Ihc habitats of 011岬1111'1(1 11附 1/Q.~fJρ加印刷d the infection

rate with S. 1111101';('1/111 in Katayama distriCl， Hiroshima Prefecture. Supplement， The

occurrence of l'al'm!osslIn山 SlII(lII('!tollr;rll.c. K)'IIIIII; 11/0， 13 (3). I 4. (in Ja岡田叫

144. OKAsE， K. (1942): Clonorchiasis in North China. f)ojillk，u 211純 111.16 (5)， 219-225. (in

Japanese with Chine鑓 刷

145. OHOI， T. (1919): Clollo/'r1l1s infection among the Formosans. With notes on the add山。n

01民間ndintermediate h帽 1of C. Silll'IISIS. Tokl-o Iji SI/IIlSlti. (21111， 6 13. (in Ja問問鍵

146. OsAFUNE， 5. (1898a): On the si:ze of shell of (.'Iol/o，-('Im egg. Oknyalllfl Il(akkfli 2nsslll

(103)， 195 224. (In J叩，l.ne!iie)

141. OSAFUNI!. S. (l898b): On the de¥'elopmenl of C. SII/('Im.(. 11111/.. 11071， 347 356; (108

8 12. (in JapJ.nesel 148. OoTA訓.S. (!89也): f¥目録。fhuman infection wilh Cfollorrltis $1111'附附 To旬。 IgnkkOl

Znsslll. B (9)， 381 384. ¥In Ja田"'制

119. OZAKI. H. (19601: NelY technic 10 demonstrate the nervous system of Glallorl'll" SlIItllSll

and on the nervous fibrils of CIOIlOrdlls demonstrated by thIs technic. 111/'0.<11111111 D(//g"kfl

K(IIbゆ19(jkllKyoslulslI /)o;，('IIi KoZlt Gyosl'klslm. (91， 27 36. (in Ja同 nese)

150. SAITO， S. (189刷 Theintemal struclUre of CloIlIIl'chi.< elZg 3n(( its l11rva. 1'1}k.lo 19nkk(/i

7.11$#11. 12 1131， 579 587. lin 片岡田副

598

151. SA1TO， 5， & M， HORI (1961): Egg production of C101IO/'d1l5 sil印刷IS in feces of the 。:開riment;¥llyinfected rabbits. KIseIrllI情。1mZ(lsshI， 10 (4)， 503. (in jap:me舘 1

152， SAITO. S. & M. HOR! (1962): Egg producing c;¥pacily of CIOllo/'rhis .~illellsis. IMd.. 1 t

(4). 272-213. (in japane明}

153. SAKAGUCI!I， K. (1956): The sludy on CIOIw/'dlIs Sillf'IISIS in the basin of the River

Onga. Ig(/kll KCllkyu， 26 (5). 1139-1164. (in japanesc with English summary)

154. SAKAI， K. (1953): On the metacercariae 回目別ticin fresh water fishes in Lake siwa

Kyolo FllrilSIl Ik(l /)a iga~' 1I Z，同 shi，56 (3)， 409-418. (in japanese with English制 mmary)

155. SATO， A.， H. SUGIHARA， K. MATSUO & L MIYASIHTA (1959): Sludy on C， sille"sis in

!shikawa Prefecture. 11. Niρ向 11 KiseicJlII G'akk仰 Nishiuiρ仰 ItShibll 1'(lihli， 15.62-64. (In

Japanese)

156. SATOMI. K， (193n: The prevalence of cJonorchiasis in 00銅 kaPrefecture. Nisshill Igaku

23 (16)， 3010 3022. (in ja開間関}

151， SAIVAOA. T. (192.')): Glycog四 and fat in trernatodes at四 riousdeveloprnental stages Alchi Igakklliノ'(lssM，32 (6)， 1088-1133. (in japanese)

158. SAWAOA. T. (1926): Glycogen and fal in senile CIOllordtis $i ;tf'lI si.~. 1'"わυ1)1Shiil叫ん

(2454)， 231-234. (in japanese)

159， SEKIGUCHI， G" S. OZU， C. AlDA & R. URYU (1963): Studies on ClolIQrdlis Silll'lIsis in

Saitarna Prefecture. 1. On the human infection， distrihution of its hosl snail and occur-

rence of its metacercariae in the fresh water fishes in the easl lowland areas. /(iscirllllJ!akll

乙附shi，12 (5)， 426-435. (in japanese with Engl同h剖 mmary)

160， SH1BA， N， (1934): The Genus slllil!llls in Korea and Manchuria， VCIIIIS， 4 (4)， 241-257

(in 1apanese)

161. SlHBANO， 1. (1933): The distribution of the first intermediate host of じ'10 110 1'(/';5 則!lf' II$I.~ ，

POr(lfOSS(/f'IIl川 II/OIIChOllriclI!';， in the vicin町。fLake Kahoku-gata， Ishikawa Prefecture

Ibul.. 38 (11)， 3351. (in japanese)

162. SHIBASONO，I. & N. HASUI (1916): A biological study on Clo/l(J/ dtis sIllcusis (First re凹 n)

Okayama Ig(lkkai Zasshi， (314)， 202-241. (in Japanese)

1日 SUGIHARA，H. (1954a): An observation on the growth of p，作m!os:mr/ll川 !ll(IlIdtOllri"tsin

the laboratory. Igakll 10 SeibulsIIgakll. 33 (6)， 265-269. (in 1apanese)

164. SUGIIIARA， H， (l954b): Taxonomical study on Parafossμ/'Illlls l!IallchQllriclIS in japan

/(yolo FurilSII I伽 JωigakllZasslti， 56 (3)， 512-516. (in 1apanese wI¥h English制附¥ary)

165. SUZUKI， M. (1935): A consideration on the disε:Qvery of CfollQl'chis siu印 sisin Japan. 1

11. 1'0旬。 IjiSltillslti， (2943)， 2164-2161: (2944)， 2209-2214. {in 1ap!ln俗的

166. TAKAGI， K. (I~渇O) : Studies on the detailed morphology of Clol/o/'cltis ullclIsis. Kiseichllgakll

Zasslti， 9 (4). 361-368. (in 1apanese)

161. TAKAG!， K. (1962): Studies on histochemical changes in adult worms of CI

1-31. (in japanese with English sumrnary)

168. TAKAGI， K. (1962): Morphological studies on Clollo/'cltis sillcIIsh. Tokllshilllll J. Hxt Med.， 9 (1)， 60-66

169. TAKAYA， Y. & D. AOKl (1936): Ear!y record of liver fluke disease in Kiushi. Miyagi

Prefecture. CllIIgai Iji Shil/to， (1235)， 398-413: (1236)， 47ト473:(1231)， 5曲 一516.(in 1a岡田，<)

110. TAKAYAMA， H. (1941): The relationship between the liver ar干dthe parasite (1) The development of Clollorchi，~ SII/打開Isby pancreas brockade. Niρρ011 K isridw Gflkkai Kリt

13， 65-66. (in japane叫

111. TAKAYAMA. H. (1942): The dcvelopment of CIOlIorc/lI's SiJlI'IISis by pancreas brockade (continued). lbid.， 14. 86-81， (in japanese)

112. UjllE， N. (1936): On the process of egg-shell formation of Clollol'chis UIlf'II$lS. '/'lIil<'(11/

Igakkfli 7.flSS“35 (8)， 18田-1896.(in japanese with English Slll¥¥mary) 173. VERDUN， P. & L. sRUYANT (1908¥: Sur la dualite spec焔quede la douve de Chine

tι'''I/o/'l'hi，. ，<iltf'IISis (COBBOLO)). !lrcltitJ. r!c 1仇 1'(I$il" 12. 99-124

599

174. VOCEL， 1-1. (1934): Der Entwicklungszyklus '1011 0ρiSlhurrhis felill e ll.~ (Riv.) nebst

Bernerkungen uber die Syslematik und Ep凶emiologie. ZQolQgicu， 33 175. WATANAllE. H. (1942): The histochemical nature of the excrelOry corpuscles in

metace閃 arieof trematodes. SI/(lIIg!ltu ShiulII Kagakll /(elll.')'ujo 1110， 12 (4)， 289-294.(ill

片岡nesewith English sumnlary)

176. WATANAsι11. (19同3):011 the size of cysts and its variation ofωme metacercaria of

"叩latod田 Ibul" 13 (1). (ill japanese with English summary)

177. WVKQFf" D. E. (1958): Studies 011 Clollorcllis sincmis IIJ. The host-parasite relations in the rabbit and observations 011 the relative susceptibility of certain Jaboratory hosts

j. P(lr(lsil.， 44 (5)， 461-466 178 、VYKO~'P. D. E. (I959): Studies 011 ClollorrnIs sIncnsIs IV. Production of eggs in

experimentaJly infeaed rabbits. J. I加川il.，45 (1)， 91-94

179. WVKQFF， D. E. & LEPES. T. J. (1957): Studies on CIOllorchIs山 'I"'$;SI. Observations

。nthe route of migration in the de1initive host. Am. J. Troρ Mcd. H)"g.. 6. 1061-1065 180. YAMA(;U引。 S.(¥935): Ober die Cercaria von CIOlIQrrh;s sill仰附$ (COsIlOLD). Z. Parllsil

8 (2)， 183-187. (in German)

l山8剖1. YOS!!川l川IωDA，T. (19幻30的) υ "， d由"凶凶}

das Mensche朗，. 0ん臼，的Bり')"11仰仰m附11r匂g'叫kk加0仰;z，ο旧"幼h;九， 42(川1川).2勾泡加0肝7.(in Jap凹温""問"聡ew刷"山hGerman s凹u山mma町Y叩y))

1凶82 、。s剖}“川l1DA.l'、(1931): Experimentel】11怜eUnlersuchung uber die B目dingungenfur die Einwan

derungen von Clollol"chis sillclIsis In den Ductus Pancre泡ticus. fhid.， 43 (4)， 920-934. (in

Japanese with German summary)

183. YOSHINO， K. (1940): Die Untersuchungen uber die enzystierten Zerkarien von Trematoden

in CarflSsills carassills仏 ). Ober die jahrzeitJichen verandrungen der enzystierten

zerkarien von Trematoden in Camssills caJ"(Jssills (L.). lbid.， 52問。 274-308;52 (3)， 548-592;日 (5)，1144-1188; 52 (6)， 1355-1390. (in Japanese with German summary)

18~. YUMOTO， Y. (1934).; The egg-production of C 針 lIellsisand its clin比almeaning. Taiμ'(111

1"帥 aiZasslli， 33 (12)， 1851-1852. (in Japanese with English summary)

185. YUMOTO， Y. (1936a): On the mi削除 structureof the egg-shells of Clollorr.flIs sintllsis and on its abnormal eggs. Taiz"1II1 Ig(lkklli ZlIsshi， 35 (8)， 1836-1846. (in Japane港e with

English summary) 186. YUMOTO， Y. (l936b): On the abnormal eggs of CloJ/u，.dlis si"clIsis. TaiwfllI 19ak帥 J

211s山hi，35 (8)， 1908. (in Japanese)

187. ANNANDALE， N. & B. PRASIIAD (1924); Rop::>rt Ofl a small collection of !llollusca 針。m

the Chekiang Province of China. Proc. l¥1al. Soc. Lomf.， 16. 27-<19

188. INATOMJ， 5.， D. 5AKUMOTO， K. ITANO & T. TSUBOTA (19“): The ultrastructure of the cercaria of CIOlIor(/lis SIIII!IISi.f (COBHOLD， 1875) LOOSE， 1907. I<iseirll/lgak/l Zasshi， 13

(3)， 337-338. (in Japanese)

189. KAKE1， S.， K. MAEKAWA & T. FUKASE (1921): Study on prevention of clonorchiasis

NippolI Nllik(fg(fklf Znsshi， 9 (6)， 375-381. (in Japanese)

190. KATSURADA， F. (1892): Pathology of c1onor山田崎1. TQk)"o Ig.叫ん。iZ(lsshi. 6 (問 9ー

32. (in Japanese) 191. KOGA， 1. (1922): The diffe閃 ntiationof various encysted metacercariae in the body of

the second川 termediatehost. Tokyo lji SIIiIlShi， (2286)， 1370-1375. (in Japanese)

192. MUTO， M. (1920): Invωtigation on helminth parasitωof dogs， cats， and mice in the

endemic area of cl加 orchiasis. T，仲間 ljiShillShi， (2188)， 1-10. (in Japanese)

193. NA(;ANO， K. (1925a): The development of CloJ/ol"chis siJleJ/sis. Tr. Biellll. COIぽr.，(6th

Tokyo)， 281

l例 NAGAND，K. (1925b): Studies on the problems of CIOIlQrchis SIJIC./US. -rl". BieJ/lI. COlIgr (6th Tokyo)， 375-385

195. NAGANO， K. (1936): Some experiments on ClOJlorchis metacercaria. Nゅρ011Kise;cJllrg(lkk(lI Kiji， 8， 67. (in Japanese)

6回

196. OoTSU削 M.，S. SA1TO， K. HASeGAWA & ~.1. 1I0Rl (1963); Epidε'niological surveys of

ClOllorclli5 $;'/('11$;5 in Niigata Prefectllre， Japan. Kis('lcllII/t"kllノ055111.12 (3). 196-202

lin Japanese with English slImmary)