ISSN 0031-0204

T ransactions and Proceedingsof thePalaeontological Society of Japan
New SeriesNo. 110

P alaeontolog ical Society of Japa n

JLIne 30, 1978

EditorItaru HAYAMI

A ssociate editors Tsunemasa SAITO and Tomowo OZAWA

Officers for 1977 - 1978
Honorary President : Teiichi KOB AYASHI
President:

Ryuzo TORIYAMA

Councillors: Kazuo ASAMA, Kiyot a ka CHINZEI, Takashi HA fA DA, Tetsuro HANAI,
Itaru HAY AMI, Syozo HAYASAKA, Hisayoshi IGO, Tadao KAMEl, Kametoshi
KANMERA, Tamio KOTAKA, Tatsuro MATSUMOTO, Tsugio SHU TO, Yokichi
TAKAYANAGI, Toshimas a T ANAI, Hiroshi DnrE
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The fossil on the cover:Original fi g ure of Podo zamites Reinii GEYLER,

1877, from the Tetori g roup. GEYLER'S description marked the onset ofmodern palaeontology in Ja pan.

All communications relating to this Jo urnal should be addressed to the
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Trans. Proc. Palaeont. Soc. Japan, N. S., No. 110, pp. 297-305, pIs. 40, 41, June 30, 1978

688. TRIASSIC CORALS FROM MT. DAIFUGEN, NARA
PREFECTURE, SOUTHWEST JAPAN*
HISASHI OKUDA
Osaka be Primary School, Yao City, 581

and
NOBUO YAMAGIWA
Department of Earth Science, Osaka Kyoiku University, Osaka City, 543

Abstract. Nine species including one new species and one new subspecies ofhexacoral described in this article were found from "limestone blocks" which arecontained in greenstone at Wasabidani in the eastern part of Mt. Daifugen, Nara
Prefecture, Southwest Japan. Judging from the paleontological data, we consider
that the age of the present hexacoral assemblage is Late Triassic.

Introduction and geological summary

The A formation (450 m+ thick) is
characterized by sandstone, and alternationof mudstone and sandstone. No fossil
occurs in this formation. The boundary
between the A and B formations is considered to be a fault with a gentle dip
nearly parallel to their bedding planes.
The B formation (100-450 m+ thick)consists of greenstone. chert and limestone.
Late Triassic hexacorals and Middle
Permian fusulinids (Y abeina globosa andothers) are found from "subangular limestone blocks" of pebble to boulder size
contained in greenstone. From the evidence of the hexacoral assemblage, thisformation may be Late Triassic or
younger. It is overlain conformably by
the C formation.
The C formation (700 m+ thick) is
composed mainly of sandstone and chert.
and subordinately associating mudstone
and greenstone. No fossil has been found.
According to the Yamato Omine
Research Group, the A formation geotec-

Recently, some hexacorals and fusulinids
were collected by the members of the
Yamato Omine Research Group from"limestone blocks" which are contained ingreenstone at Wasabidani (Wasabi Valley)in the eastern part of Mt. Daifugen, Nara
Prefecture. Southwest Japan. In this article nine species including one new species ane! one new subspecies of hexacorals
are described, and the age of the hexacoral
assemblage is discussed.
The geology around Mt. Daifugen wasinvestigated by SHIIDA (1962) and the
Yamato Omine Research Group (1976).
According to the Yamato Omine ResearchGroup, the strata of this area can bedivided into three formations called A, B
ane! C at Wasabidani. They have ageneral strike of N 60 -80 E and dip
northward at about 5-20 degrees.
00*Received June 30, 1977; read Jan. 30, 1976
at Naruko.

297

Hisashi OKUDA and Nobuo YAMAGIWA

298

AlIIJ]
136°E
Text-fig. 1. Index map of Mt. Daifugen.
S: Sambagawa belt, C: Chichbu belt, Sh:
Shimanto belt, MTL: Median tectonic line.

tonically belongs to the Shimanto belt,
and the Band C to the southern subbelt
in the Chichibu belt. Therefore, thefault between the A and B formations
corresponds to the Butsuzo tectonic line.

Table 1.

c~

Text-fig. 2. Map showing the fossil localities at Wasabidani in Mt. Daifugen.
A: A formation, B: B formation, C:
C formation.

Palaeontology and correlation

Some hexacorals were discovered fromthree localities (text-figs_ 2,3) at Wasabidani (Table 1).
1) Species from loco 1
Montlivaltia norica ominensis subsp. nov.
resembles M. norica norica. The latter
was reported by FRECH (1890) from the
Zlambach Formation in Austria, by VINASSA

List of Late Triassic corals from Mt. Daifugen.

~'Loc. 1

Loc. 2

Loc. 3Species and subspecies

Montlivaltia norica ominensis subsp. nov.

x

M. sp. aff_ M. stylophylloidesx

M. sp. indet.

x

Thecosmilia wasabidaniensis sp. nov.

x

T. sp. aff. T. eguchii

x

Pinacophyllum ? sp. indet.

x

Thamnastrea (Thamnastrea) sp. indet.

x

Procyciolites ? sp. indet.

x

Isastrea sp. aff. I. majorx

I. sp. indet.

x

Procyc1olitidae gen. sp_ indet.

x

688.

Triassic Corals from Mt. Daif1,tgen(1915) from the Upper Triassic at Pualaca,
Timor, by SMITH (1927) and SQUIRES (1956)
from Carno-Norian in Idaho, Oregon andAlaska. It is also similar to the species
described by KANMERA (1964) as Montlivaliia sp. cf. M. norica from the Koguchi
Formation of the Konose Group, Kyusyu,
Japan.
Montlivaltia sp. indet. is related to M.
styloPhylloides from the Upper Triassic
in Timor (VINASSA, 1915) and M. sp. d.
M. stylophylloides from the Koguchi Formation of the Konose Group (KANMERA,
1964).
Thecosmilia wasabidaniensis sp. nov.
resembles T. badiotica from the St. Cassian Formation in southern Tyrol (VOLl,
1896). It is also allied to Thecosmilia
eguchii from the Koguchi Formation of
the Konose Group (KANMERA, 1964).
Thecosmilia sp. aff. T. eguchii is allied
to T. eguchii described by KANMERA (1964).
The latter occurs in the Koguchi Formation of the Konose Group.
Pinacophyllum ? sp. indet. is similar to
P. gracile reported by VOLl (1896) from
St. Cassian Formation in southern Tyrol.
Isastrea sp. aff. I. major is related to
I. major from the Zlambach Formation(FRECH, 1890) and the Carno-Norian in
Idaho (SQUIRES 1956). It is also similar
to Elyastraea? sp. from the Koguchi Formation of the Konose Group (KANMERA,
1964).
Isastrea sp. indet. resembles I. austriaca
var. sprendes FRECH (1890) from the
Zlambach Formation, I. guembeli var.
minor VINASSA (1915) from the Upper
Triassic in Timor and Actinastrea? sp.
indet. by YAMAGIWA (1963) from theUpper Triassic in Timor.
Thamnasteria (Thamnasteria) sp. indet.
closely resembles T. (T.) sp. from the
Koguchi Formation of the Konose Group(KANMERA, 1964) and T. (T.) loretzi from
St. Cassian Formation in southern Tyrol

299(VOLl, 1896).
2) Species from loco 2Montlivaltia sp. aff. M. styloPhylloides
is similar to M. stylophylloides. The
latter was reported by VINASSA (1915)
from the Upper Triassic in Timor. The
present species also resembles Montlivaltia
sp. d. M. stylophylloides from the Koguchi
Formation of the Konose Group (KANMERA, 1964).
Procyclolites? sp. indet. resembles P.
timoricus described by VINASSA (1915)
from the Upper Triassic in Timor and P.
? sp. aff. P. timoricus by KANMERA (1964)
from the Koguchi Formation of theKonose Group.
In addition, fusulinids such as Yabeina
globosa and Schwagerininae gen. and sp.
indet. were found from other limestone
blocks at the same locality.
3) Species from loco 3
One species belonging to the family
Procyclolitidae occurs at this locality.
As its generic assignment is not yet
clear, it is not described in this article.
It appears to resemble the species described by KANMERA (1964) as Procyclolites
sp. d. P. triadicus from the Koguchi
Formation of the Konose Group.
Some fusulinids such as Yabeina globosa,Colania sp. indet., Reichelina sp. indet. etc.
were obtained from other limestone blocks
at the same locality.
Judging from the above mentioned
palaeontological data at the three localities,
the present hexacoral assemblage show
certain affinity with those from the
Zlambach Formation of Rhaetian (-Late
Norian) age in Austria, the St. Cassian
Formation of Carnian age in southern
Tyrol, the Carno-Norian in northwestern
North America, the Upper Triassic at
Pualaca, Timor and the Carno-Norian
Koguchi Formation of the Konose group,
Kyusyu, Japan. Therefore, we consider
that the age of the present coral assem-

Hisashi OKUDA and Nobuo YAMAGIWA

300

Order Scleractinia BOURNE, 1900
Suborder Faviina VAUGHAN
and WELLS, 1943
Superfamily Faviicae GREGORY, 1900
Family Montlivaltiidae DIETRICH, 1926
Subfamily Montlivaltiinae DIETRICH. 1926
Genus Montlivaltia LAMOUROUX, 1821
M ontlivaltia norica ominensis
subsp. nov.
PI. 40, figs. 1,2

1[] 2~ 3~

o

I""

100m

I,!,. I

Text-fig. 3. Columnar sections at
Wasabidani in Mt. Daifugen.
1. Sandstone, 2. Alternation of sandstone
and mudstone, 3. Mudstone, 4. Limestone,
5. Chert, 6. Greenstone, 7. Fossil locality,
A: A formation, B: B formation, C: C formation.

blage is Late Triassic.
Acknowledgements

We wish to express our hearty thanks
to Professor Koichiro ICHIKAWA of the
Osaka City University for his kind guidanceand critical reading of the manuscript,
to Dr. Akira YAO of the Osaka City
University who gave us kind advice andto the members of the Yamato Omine
Research Group who permitted us to study
some interesting materials collected bythem.
Systematic description

Corallum simple. Corallite subcircularin transverse section; about 33.0 mm in
the shortest diameter. Corallite wall
distinct, mostly 0.5 to 1.0 mm in thickness. Septa straight or slightly sinuous,and numerous, about 250 in number,arranged in seven cycles. Septa of thefirst four cycles reach or nearly reachthe central part of the corallite, notmeeting in a point but on a line, keepingwith the elliptical form. Septa of thefirst two cycles are thick, and those of
the fifth to seventh cycles thinner than
the first four. Those of the fifth cycle
are about three-fourths to two-thirds ofthe radius of corallite, those of the sixth
cycle generally shorter than a half of theradius, and those of the seventh cycle
very short or rudimentary. Columellaindistinct. Dissepiments distinct.
In longitudinal section, dissepiments
show somewhat elongate form with theirconvex sides facing inwards as well as
upwards.
Comparison: The present new subspecies is similar to Montlivaltia norica
norica described by FRECH (1890, pp. 39-40,
pI. 3, figs. 8, 9, pI. 10, figs. 1-5, pI. 13,
figs. 1-7, pI. 18, figs. 17, 17a) in many
respects. However, its septa are much

688. Triassic Corals from kIt. Daifugen
more numerous, and its dissepiments
show somewhat elongate form with theirconvex sides facing inwards as well as
upwards and larger size in longitudinal
section. It is also related to Montlivaltia
norica norica by SMITH (1927, pp. 126127, pI. 111, fig. 10) and SQUIRES (1956,
p. 21, figs. 32-47), but differs fromthe latter in having much more numerous
septa and larger corallite. It is separablefrom Montlivaltia sp. cf. M. norica norica
by KANMERA (1964, pp. 120-121, pI. 12,
figs. 6-10) in having much more numerous septa, larger corallite and thicker
corallite wall.
Repository: OMNH (Osaka Museum of
Natural History), M341 (holotype).
Montlivaltia sp. aff. M. stylophylloides
VINASSA
PI. 40, fig. 3

Aff.1915. Montlivaltia stylophyiloides VINASSA,
Pal. Timor, vol. 4, no. 8, pp. 100-101,
pI. 6, figs. 3-6.
1964. Montlivaltia sp. d. M. stylophyiloides,
KANMERA, Mem. Pac. Sci., Kyusyu Univ.,
ser. D, vol. 15, no. 1, pp. 123-124, pI. 12,
figs. 1-3.

Corallum simple. Corallite subellipticalin transverse section; 13.0 mm in the
shortest diameter and 23.0 mm in thelongest. Corallite wall missing. Septa
very thick, straight or slightly flexuous;
they show elongate fusiform in shape intransverse section, about 48 in number,arranged in five cycles. Septa of thefirst three cycles about 20 in number,
extending to or near the central part ofcorallite. Those of the fourth cycle twothirds to a half of the radius. Septa of
the fifth cycle less numerous and very
short.
Synapticulae and dissepiments
develop. No columella. There is no301

longitudinal section.
Comparison: The present species resembles M ontlivaltia stylophylloides described by VINASSA (1915, pp. 100-101, pI.
6, figs. 3-6) and M. sp. cf. M. stylophylloides by KANMERA (1964, pp. 123-124, pI.
12, figs. 1-3) in many important characters. The former differs, however, fromthe latter two in having smaller corallite
and more distinct synapticulae.
Repository: OMNH, M342.
Montlivaltia sp. indet.
PI. 40, fig. 4

Corallum simple. Corallite subcircularin transverse section; 12.0 mm and 15.0mm in the shortest and longest diameter.
Corallite wall is recognized in part, being
0.1-0.2 mm in thickness. Septa straightor slightly flexuous; thick near the corallite wall, thinning towards both ends.
Septa about 68 in number, arranged infive cycles. About 14-15 septa of thefirst two cycles reach the central part ofthe corallite. Those of the third cycle
slightly shorter than the first two. Thoseof the fourth cycle one-third to two-thirdsof the length of the first two. Those of
the fifth cycle very short or rudimentary.
Synapticulae and dissepiments present.
No longitudinal section is seen.
Comparison: It is related to Montlivaltia stylophylloides VINASSA (1915, pp. 100101, pI. 6, figs. 3-6) and the allied species(KAN:VIERA, 1964, pp. 123-124, pI. 2, figs.
1-3; OKUDA and Y AMAGIWA, this article).
However, the former one can be distinguished from the latter ones in thefollowing characters, 1) more numerous
septa, 2) different shape of septa, 3)
smaller corallite.
Repositoryy: OMNH, M343.

302

Hisashi OKUDA and Nobuo YAMAGIWA
Genus Thecosmilia M. EDWARDS
and HAIME, 1848

Thecosmilia wasabidaniensis sp. nov.
PI. 40, fig. 5

Corallum fasciculate. Corallites subcircular in transverse section; usually
6.5-8.5 mm in diameter. Corallite wallthin, mostly 0.1 mm. Septa 54-80 in
number, arranged in four or five cycles,
almost straight, and thick in the middle
part, thinning towards both ends. About
16-18 septa of the first two cycles reachthe central part of the corallite, those of
the third cycle near the central part, andthe fouth cycle about a half as long as theradius; those of the fifth cycle short andthin, mostly rudimentary. Dissepiments
numerous. Synapticulae scarce. Columellaabsent. There is no longitudinal section.
Comparison: The present new species
is allied to Thecosmilia eguchii KANMERA(1964, pp. 124-125, pI. 17, figs. 1-7, pI. 18,
fig. 7) in many respects, but differs fromthe latter in having thick septa in the
middle part and larger corallites. It isalso similar to Thecosmilia badiotica VOLZ
(1896, pp. 26-30, pI. 2, figs. 14-19), butdiffers in its thinner corallite wall andthick septa in the middle part.
Repository: OMNH, M344 (holotype).

Thecosmia sp. aff. T. eguchii KANMERA
PI. 40, fig. 6

Aff.1964. Thecosmilia eguchii KAN~IERA, Mem.
Fac. Sci., Kyusyu Univ., Ser. D, vol. 15,
no. 1, pp. 124-125, pI. 17, figs. 1-7, pI.
18, fig. 7.

The preservation of the present material
is not good. However, it resembles Thecosmila eguchii KANMERA (1964, pp. 124125, pI. 17, figs. 1-7, pI. 18, fig. 7) in thefollowing respects, 1) size and shape ofthe corallites, 2) shape, number, lengthand arrangement of the septa and 3) distinct dissepiments. Therefore, we thinkthat the former may be referable to thelatter.
Repository: OMNH, M345.
Suborder Astrocoeniina VAUGHAN
and WELLS, 1943
Family Astrocoeniidae KOBY, 1890
Subfamily Pinacophyllinae VAUGHAN
and WELLS, 1943
Genus Pinacophyllum FRECH, 1890
Pinacophyllum ? sp. indet.
PI. 41, fig. 1

Explanation of Plate 40
Figs. 1-2. Montlivaltia norica ominensis subsp. nov.
1. Transverse section ..... " ....................... , ............... x 2.0 (OMNH, M341a)
2. Longitudinal section ............................................ x 3.0 (OMNH, M341b)
Fig. 3. Montlivaltia sp. aff. M. stylophylloides VINASSA
3. Transverse section .............................................. x 3.0 (OMNH, M342)
Fig. 4. Montlivaltia sp. indet.
4. Transverse section .............................................. x 3.0 (OMNH, M343)
Fig. 5. Thecosmilia wasabidaniensis sp. nov.
5. Transverse section .............................................. x 3.0 (OMNH, M344)
Fig. 6. Thecosmilia sp. aff. T. eguchii KANMERA
6. Transverse section .............................................. x 3.0 (OMNH, M345)

OKUDAand YAMAGIWA:

Late Triassic corals

Plate 40

688.

Triassic Corals from Mt. Daijugen

Corallum probably fasciculate, subcircular in transverse section, with shortest
diameter of about 6.5 mm. Corallite wall
distinct and thick. Septa 34 in number
and straight or slightly sinuous; most ofthem two-thirds to a half of the radius of
the corallite in length. They graduallythinning distally, and very thick in peripheral area, so as to be laterally in contact with the neighbouring ones. No columella. No longitudinal section.
Comparison: It has only one corallite.
Except for this point, it is related tothe species of the genus Pinacophyllum inmany important characters. It is allied to
Pinacophyllum gracile described by VOLZ
(1896, pp. 82-84, pI. 10, figs. 14-28). However, the latter has smaller corallites than
the former, and consists of fasiculate corallum.
Repository: OMNH, M346.

303

the following characters, 1) small corallites, 2) not numerous septa, 3) abundant
synapticulae, 4) geniculated septa, 5) distinct columella. The features mentioned
above practically agree with those ofThamnasteria (Thamnasteria) sp. describedby KANMERA (1964, pp. 134-135, pI.
13, figs. 6-9).
It is also similar toThamnasteria (Thamnasteria) loretzi VOLZ
(1896, pp. 59-60, pI. 6, figs. 12, 12a-c), butdiffers from the latter in having smallercorallites and less numerous septa.
Repository: OMNH. M347.
Suborder Fungiina VERRILL, 1865
Superfamily Agariciicae GRAY, 1847
Family Procyclolitidae VAUGHAN
and WELLS, 1943
Genus Procyclolites FRECH, 1890

Family Thamnasteriidae VAUGHAN
and WELLS, 1943
Genus Thamnasteria LESAUVAGE, 1823
Subgenus Thamnasteria LESAUVAGE, 1823
Thamnasteria (Thamnasteria) sp. indet.
PI. 41, fig. 2

Corallum massive and thamnasterioid.
Corallites variable in size; central distance
1.0-2.2 mm. Septa relatively thin, confluent with those of the adjacent corallites,
15-24 in number; about 10-12 of themextending to the central part of corallite,
and some of them join with a columella.
They slightly sinuous or geniculate; perforations generally scarce. Synapticulae
well observed. Columella distinct, subelliptical to subcircular in transverse section; about 0.10-0.15 mm in shortest diameter. No longitudinal section is seen.
Comparison: The present material has

Procyclolites ? sp. indet.
PI. 41, fig. 3

Corallum simple. Corallite probably subcircular in transverse section; Radius of thecorallite about 12.0mm. Corallite wall thin,recognizable in part. Septa thin, straightor slightly flexuous, and numerous, about
35 in number in a quadrant circular of
the corallite; those of the first two cycles
reach the central part, those of the third
cycle near the central part, those of the
fourth two-thirds of the radius, and thoseof the fifth shorter than a half of theradius or rudimentary. Synapticulae anddissepiments present. Columella indistinct.
There is no longitudinal section.
Comparison: The present specimen resembles the species described by VINASSA(1915, pp. 101-102, pI. 9, figs. 11-13) as
Myriophyllia timorica in many respects.
However, it is represented only by One
incomplete transverse section, and is notHisashi OKUDA and Nobuo YAMAGIWA

304

well preserved. It is also related to Procyclolites ? sp. aff. P. timoricus by KANMERA (1964, pp. 131-132, pI. 13, figs. 1-5),
but differs in larger corallite and more
numerous septa.
Repository: OMNH, M348.
Family Calamophyllidae VAUGHAN
and WELLS, 1943
Genus I sastrea M. EDWARDS
and HAIME, 1851

Isastrea sp. aff. I. major FRECH
PI. 41, fig. 4

Aff.1890. Isastrea profunda var. major FRECH. Palaeontographica, vol. 37, pp. 22-23, pI. 5,
figs. 4,5.
1956. Elysastraea major SQUIRES. Amer. Mu·
seum Novitates, no. 1797, p.26, figs. 52,
53.

Corallum massive and cerioid. Corallites
mostly pentagonal or hexagonal in shapein transverse section; some of them tend
to be elongate, measuring 3.0 to 4.0 mm
in the shortest diameter, 5.5 to 8.5 mm in
the longest. Corallite wall relatively thick.
Septa 40 to 50 in number and straight orslightly sinuous, having distinct spines on

their lateral surfaces; some of the spines
connected with those of the neighbouring
septa, forming synapticulae. Most septaof the first two or three cycles rather
thick, extending to or near the central
part of the corallite. Those of the fourth
cycle thin and about a half of the radius.
Those of the fifth poorly developed, butabsent in immature stage. Dissepiments
present. Columella indistinct. No logitudinal section is seen.
Comparison: The present species resembles Isastrea major FRECH (1890, pp.
22-23, pI. 5, figs. 4, 5; SQUIRES, 1956, p.
26, figs. 52, 53) in many important characters. However, the present material is
not well preserved, and its corallites are
somewhat smaller than those of thatspecies. It is somewhat related to Elyastraea ? sp. by KANMERA (1964, p. 129, pI.
13, fig. 11), but differs from the that species in having different shape of septa.
It is distinguished from Isasrea sp. indet.
(OKUDA and YAMAGIWA, this paper) in
having larger corallites and more numerous septa.
Repository: OMNH, M349.

I sastrea sp. indet.
PI. 41, figs. 5, 6

Corallum massive and cerioid, mostly

Explanation of Plate 41
Fig. 1. Pinacophyllum? sp. indet.
1. Transverse section .............................................. x 3.0 (OMNH, M346)
Fig. 2. Thamnasteria (Thamnasteria) sp. indet.
2. Transverse section .............................................. x 3.0 (OMN"H, M347)
Fig. 3. Procyclolites? sp. indet.
3. Transverse section .............................................. x 3.0 (OMNH, M348)
Fig. 4. Isastrea sp. aft. I. major FRECH
4. Transverse section .............................................. x 3.0 (OMNH, M349)
Figs. 5-6. Isastrea sp. indet.
5. Transverse section .............................................. x 3.0 (OMNH, M350a)
6. Longitudinal (somewhat oblique) section ....................... x 3.0 (OMNH, M350b)

OKUDA

4

and YAMAGIWA:

Late Triassic comls

Plate 41

688.

Triassic Comls from Mt. Daifugenwith pentagonal or hexagonal corallites;
generally 1.5 to 2.3 mm in the shortest
diameter. Thick corallite wall present,
but partly absent with confluent septa.
Septa rather thin and straight or gently
flexuous. They have distinct processeson their lateral surfaces, and some of theprocesses connected with those of theadjacent septa. Corallites 30-38 in number, about 12 of them extending to thecentral part. Dissepiments present. Columella indistinct. Longitudinal (somewhat
oblique) section present.
Comparison: It is similar to Isastrea
austriaca var. splendes described by FRECH(1890, p. 24) in many respects. However,the former may be distinguished from thelatter in having thicker corallite wall. It
is also related to I sastrea guembeli var.
minor by VINASSA (1915, p. 96, pI. 10, figs.
3-5). It differs, however, in having more
numerous septa. It is somewhat allied toActinastrea ? sp. indet. by Y AMAGIW A(1963, p. 85, pI. 1, figs. 6, 7). However,
the rna terial of that species is poorly
preserved.
Repository: OMNH, M350.
References
FRECH, F. (1890): Di" Korall~nfauna der
Trias. 1. Die Korall<3n der Juvavischen
Triasprovinz. Palaeontographica, vol. 37,
p. 1-116, pis. 1-21.

*1If'M,

Daifugendani, !1I~:fr

Koguchi 'J'i=l,305

KAr-::VIERA, K. (1964): Triassic coral faunafrom the Konose group in Kyusyu. Mem.
Fac. Sci., Kyusyu Univ., ser. D, vol. 1",
no. 1, p. 117-147, pis. 12-19.
SlIllDA, 1. (1962): Stratigraphical and geo·
tectonic studies of the Paleozoic Chichibu
and the Mesozoic Hitaka (Shimanto) terrains in the central part of the Kii Moun·tainland, Southern Kinki, Japan. Research
BUll. (Dep. Cen. Educ., Nagoya Univ.),
no. 6, Separate vol. 1, p. 1-58. (J).
S~IITJ-I, J. P. (1927): Upper Triassic marine
invertebrate fanna of North America. U.
S. Ceol. Surv., Prof. Paper 1-11, p. 1-262,
pis. 1-121.
SQuIRES, D. F. (19,,6): A new Triassic faunafrom Idaho. Amer. lvfuseul1l Novitates, no.
1797, p. 1-27.
VINASSA DE REGNY, P. (1915): Triadische
Algen, Spongien, Anthozoen und Bryozoen
aus Timor. Pal. Timor, vol. 4, no. 8,
p. 73-118, pis. 1-10.
VOLZ, W. (1896): Die Korallenfauna der
Trias. II. Die Korallen der Schicht<3n von
St. Cassian in Siid-Tirol. Palaeontographica,
vol. tl3, p. 1-124, pis. 1-11.
Y A:VIAGIWA, N. (1963): Some Triassic corals
from Portuguese Timor (PalaeontologicalStudy of Portuguese Timor (II». Mem.
Osalw Univ. Lib. Art. and Educ., no. 12,
p. 83-86, pl. l'
YA~IATO O~II"E RESEARCH GHOUl' (1976) : Paleozoic and Mesozoic systems in the central area of the Kii Mountains, Southwest Japan. pt. 1. Geology around Mt.
Daifugen district, Nara Prefecture. Chikyu
Kagaku, vol. 30, no. 5, p. 260-267. (J).

Konose :f!j1ij!J[,

Omine

**,

Yamato ~k:fl-1,

Wasabi-JJHH~*lll[-~lffiil' ~gjUJj L U&J~ll- Y 7 7-. ff:i3l]llflill{t;Pi~:' -:>t, -C:~ri!iJfdctlfTff6-:~nmv:'&UfI:-r-:Q !1I~:frO)tRfS:!6:m"pO)li!\l1;jk1:1)J(:'r"b>j> ~*fi1**liJf5E fl' 'v - 7'~:' .t ..., -C:l*~ <'!: tLf-::hlH
J]Il]fIiIl{t1:1~liJf~ L, 1 ~HI~.h> <ts9:fi1!:f5.tlf 1 ~jffi:fil!~~i3Jf~¥IH!;r-r-:Q t:t!<i:', -ttL~~±'f4;
t -r-:Q :hM1AlJJi\JHt1:1ll'f~0)1f-~tJ~1&Jm I- Y 7 7-.ff:i3~ Lco-r-;: C ~~fili~ L L~ II:!
~Jj. !1I~}lli:;JcTrans. Proc. Palaeont. Soc. Japan, N. S., No. 110, pp. 306-318, pI. 42, June 30, 1978

689.

A NEW TEXANITINE AMMONITE FROM HOKKAIDO(STUDIES OF CRETACEOUS AMMONITES FROMHOKKAIDO AND SAGHALIEN-XXXIV)"T A TSURO MATSUMOTO and YOSHIMITSU HARAGUCHI**
c/o Department of Geology, Kyushu University 33, Fukuoka 812

With Notes on the Santonian Biostratigraphy(Tatsuro MATSUMOTO)

Abstract. This is an addition to a previously published monograph of the
Texanitinae (MATSUMOTO, 1970). A new species of Texanites is described on thebasis of a recently obtained specimen from about the middle of the Santonian in
the Oyubari district, central Hokkaido. It is allied to Texanites (Texanites) hourcqui COLLIGNON, from the Middle Santonian of Madagascar, but is distinguished by
its rursiradiate, distant ribs, inequidistant configuration of tubercles and diverging
deep branches of L in the suture_
As an appendix, notes are given on the biostratigraphic subdivision and correlation of the Santonian primarily on the grounds of texanitine species.

trict of central Hokkaido, the sediments
are more clayey and seem to represent
comparatively more off-shore, somewhat
deeper facies. From this area, however,a fairly large texanitine ammonite wasreported about 50 years ago. That is
lvfortoniceras nomii Y ABE and SHIMIZU,
1925, recently revised to be called
Protexanites (Anatexanites) nomii (Y ABEand SHIMIZU) (MATSUMOTO, 1970, p.242).
Its holotype is unfortunately missing andonly its plaster cast is preserved in
Tohoku University, Sendai. The typelocality of that holotype was "the cliff
at the junction of the Shiyuparo and thePanke-mo-yuparo", which is now under
the water of an artificial lake of the
Shuparo [=Shiyuparo] dam.
While we are continuing a field workin the Oyubari district, we have soughtso far in vain any example of the same

Introduction
From the Upper Cretaceous of Japanand Saghalien altogether 23 species of
the Texanitinae, a subfamily of the
Collignoniceratidae, have hitherto been
known, of which a majority is from
Hokkaido (see MATSUMOTO, 1970). Theirmode of occurrence in the Cretaceous
muddy sediments in the basin of Hokkaido (the so-called Yezo geosyncline) is
scattered and rather isolated, although
they tend to be somewhat more common
in the probably shallower facies, forexample in fine-sandy siltstones of theHaboro-Kotambetsu-Obira areas of northwestern Hokkaido. In the Oyubari dis-

* Received August 26, 1977; read June 18,
1977 at Shizuoka.
** Present address of Y. HARAGUCHI: Meiji
Consultant Co., 3-4-22, Otemon, Fukuoka 810.
306

689. A New Texanitine Ammonite from Hokkaido
species, aside from an immature specimen from the Haboro area (MATSUMOTO,
1970, pI. 32, fig. 1). Meanwhile, one ofus (Y. H.) found another texanitine ammonate from another locality of the same
Oyubari district. This represents aninteresting new species which we describe
in this paper.
Before going further we thank Messrs.
Junichi YAZAKI, Yoshihiro MATSUBARA,
Katsuo YAMAZAKI and Katsuo IRIE ofthe Oyubari Office of the Forestry
Bureau, who gave us facilities for ourfield work. We also thank Drs. Hiromichi HIRANO and Kazushige TANABE,
who helped us in both the field andlaboratory works. Miss Mutsuko HA YASHIDA assisted us in preparing the manuscript.
Geological Setting

Fig. 1 is a geological map of thenorthern part of the Oyubari district,prepared tentatively by one of us (Y. H.).
The area is partly overlapped with andprimarily continued to the southwest of
the Shiyubari [Shiyuparo] area, mapped.35 years ago by the other of us (MATSUMOTO, 1942, pI. 13). Broadly speaking,
the Cretaceous outcrops become younger
as we go westward, but in detail thestructure is imbricated by minor thrusts
and overturned folds.
On account of this geologic structure
we see the repeated occurrence of thezones defined by the first appearance ofthe named inoceramid species as follows(in ascending order):1: Zone of Inoceramus aff. saxonicus
PETRASCHECK (temporarily called
Inoc. aff. teshioensis in our fieldwork)
2: Zone of Inoceramus hobetsensis NAGAO and MATSUMOTO
3: Zone of Inoceramus teshioensis NAGAO

307

and MATSUMOTO
4: Zone of Inoceramus uwajimensis YEHARA (closely allied to but at least
subspecifically distinguished from
Inoceramus stantoni SOKOLOW)
5: Zone of Inoceramus mihoensis MATSUMOTO (somewhat allied to Inoceramus
erectus MEEK)
6: Zone of Inoceramus (Platyceramus)
amakusensis NAGAO and MATSUMOTO
7 : Zone of Inoceramus (Cladoceramus?)japonicus NAGAO and MATSUMOTO
where zones 1, 2 and 3 are Turonian, 4
and 5 Coniacian, and 6 and 7 Santonian(see NODA and MATSUMOTO, 1976). The
described ammonite was solitarily embedded in a mudstone which is assignable
to zone 6 or 7 in the upper part of theUpper Yezo Group, exposed at a locality
not far from the outcrops of the sandstones of the Hakobuchi Group.
Palaeontological Description

Family Collignoniceratidae WRIGHT& WRIGHT, 1951

Subfamily Texanitinae COLLIGNON, 1948
Genus Texanites SPATH, 1932
Type-species:- Ammonites texanus ROEMER, 1852.
Generic diagnosis:-See MATSUMOTO,
1970, p. 266.
Remarks:-Two subgenera, Texanites
and Plesiotexanites, are distinguished(MATSUMOTO, 1970, p. 267). Nine speciesof Texanites have hitherto been describedfrom Hokkaido and other areas in Japanof which three are referable to Texanites(Texanites). The new species described
below is also assigned to Texanites(Texanites).

Tatsuro MATSUMOTO and Yoshimitsu HARAGUCHI

308

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Fig. 1. Geological map of the northern part of the Oyubari area, central Hokkaido.
1-7: Zones of Inoceramus species in asending order as indicated in the text. H: Hakobuchi Group. Thick line: Major thrust. Thick broken lines: Minor thrusts and faults:
Solid circle: Locality of the described Texanites. Abbreviations of the streams are Sy:
Shiyuparo, Sh: Shimizu-zawa, Km: Komaki-zawa, Ag: Agemaki-zawa [=Kamimaki.zawa],
am: Omaki-zawa, Ks : Kosenzawa, Pe: Penke-horoka-yuparo, Pa : Panke-horoka-yuparo. Inset
is a small map of Hokkaido, indicating Oyubari with a small solid circle. (prepared by Y.
HARAGUCIII)689.

A New Texanitine Ammonite from Hokkaido

Texanites (Texanites) yazalzii sp. nov.
PI. 42, Fig. 1; Text·fig. 2

Holotype :-GK. H5865, from loco Y1120,
collected by Yoshimitsu HARAGUCHI, now
preserved at Kyushu University.
Etymology:- This species is dedicatedto Mr. Junichi YAZAKI, former Directorof Oyubari Office, Bureau of Forestry.
Specific characters :-Shell fairly large,
about 250 mm in diameter of restored
figure, consisting of slowly ·::nlarging
evolute whorls, which are subrectangularin cross-section, higher than broad (witha proportion of height to breadth about
10 : 8), broadest in the lower part with
Umbilicus
slightly convergent flanks.
wide, surrounded by low but steep wall
and abruptly rounded shoulder.
Ribs strong, mostly somewhat rursiradiate and a few of them nearly rectiradiate, comparatively denser on the
inner whorl separated by the interspaces
which are as wide as the ribs, moderately
distant with wider interspaces on thenext whorl of probably adolescent stage,
and much distant and coarse on the bodywhorl of the adult stage. On the outer
two whorls there is as a rule intercalationor branching of the ribs. The secondary
ribs begin to appear somewhere near the
mid-flank or near the umbilical shoulder.
On the inner whorl the intercalation
seems to be less frequent.
Tubercles unequally distributed in fiverows. The distance between the first(i. e. umbilical) and the second (i. e. innerlateral) is longer than that between thesecond and the third (i. e. outer lateral),that between the third and the fourth(i. e. ventrolateral) is the shortest, and thatbetween the fourth and fifth (i. e. ventral)
is moderate. This configuration of tubercles is regularly maintained all throughthe observable three whorls.
The tubercles change with growth in309

strength and shape. On the body-whorl
and the preceding part (about 300°) of
the septate whorl the umbilical tubercles
are the most prominent, the inner lateralones on the long ribs the next in prominence, and the outer lateral the
weakest. The ventrolateral tubercles ofmoderate intensity, indistinctly clavateon the late septate whorl but not clavateon the body-whorl. The ventral tubercles narrowly clavate all through thevisible stages.
On the inner whorl (of 40 to 70 mm indiameter) the outer lateral as well as theventrolateral tubercles are clavate andsharp-headed, the inner lateral ones
indistinctly clavate and moderately strong,
and the umbilical ones small but prominent. with a bullate base.
Sutures of general texanitine patternand characterized by narrow and fairly
deep branches diverging from the reversed omega-shaped stem of L, the tallsecond lateral saddle between Land U2
much narrowed near the base of its
stem. These sutural characters appear
already on the inner whorl of about 40
mm in diameter.
J1easurements (in mm on the whorl ofadolesent stage) :Diameter Umbilicus Ikight Breadth B./H.
127.0
59.8
,11.6
17.2x20.82(1)(0.47)(0.32)(0.27)

Remarks:-One side of the specimen isincompletely preserved and the last partof the body-whorl squashed. Otherwise
the characters are well shown at successive three stages. The extent of variation is unknown at present.
Compw'ison :-Although a single specimen (holotype) is available at present. itshows distinctive characters which enable
us to regard it as representing a new
species.
This species resembles Texanites (Tex-Tatsuro MATSUMOTO and Yoshimitsu HARAGUCHI

310

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Fig. 2. Texanites yazakii sp. nov. Diagrammatic sketch of the holotype, GK. H 5856,
from loco Y 1120. Lateral view (a), in which the deformed last part is roughly outlined,with A towards anterior. Whorl-section (costal and intercostal) at the middle growthstage (b). External suture (c) at about S. (T. M. delin.)anites) hourcqui COLLIGNON (1948, p. 78,
pI. 10, fig. 1: pI. 7, fig. 1; 1966, p. 72, pI.
484, fig. 1957), from the Santonian ofMadagascar, in the fairly large, widely
umbilicate, evolute shell, slowly enlarging whorls with a subrectangular to
subtrapezoidal cross-section, and strong
straight ribs which show the intercalationor bifurcation occurring even on theadult whorl. It is, however, distinguished by its much more distant andsomewhat rursiradiate ribs on the whorlof later growth-stages and the deeper,
more diverging branches of L and thenarrowed stem of the second lateralsaddle. Tubercles are nearly equidistantin that Madagascar species, whilst they
are arranged at unequal distance in our
species as described above.

The present species is similar to
Texanites (Texanites) dic1wtomus COLLIGNON (1948, p. 80, pI. 7, fig. 2; pI. 9, fig.
3; pI. 11, fig. 1), from the Upper Santonianof Madagascar, with respect to the frequent intercalation or branching of thesecondary ribs and the deep branches
diverged from the fairly narrow stem of
L. That species from Madagascar isdistinct from ours in its more rapidly
growing whorls, narrower umbilicus,
prorsiradiate (instead of rursiradiate)
ribs, nearly equidistant configuration of
the inner three rows of tubercles andon the average less compressed whorl.
Moreover, a larger outer whorl has not
yet been reported in that Madagascar
species.
With respect to the configuration of

689.

A New Texanitine Ammonite from Hokkaido

tubercles, the distant ribbing on the outerwhorl, and the diverging branches of L,
the present species is similar to Texanites
quadrangulatus COLLIGNON (1966, p. 76,
pI. 486, fig. 1961), from the Upper andthe Middle Santonian of Madagascar, but
its whorl is distinctly more compressedthan the nearly square whorl (H.=B.) of
T. quadrangulatus and this Madagascar
species has simple, equally long ribs
without notable intercalation or branchingof the secondary rib.
The branching or intercalation of theribs is characteristic of the genus Submortoniceras, which, however, is more
involute, with rapidly growing whorls,
and the ornaments (except for the umbilical tubercles) are weakened on the outerwhorl. In the latter respect the present
species is not related with Submortoniceras.
Occurrence :-The holotype was collected by one of us (Y. H.) from the
mudstone exposed at loco Y1120 on theleft side of the creek called the Penkehoroka-yuparo, a tributary of the Shiyuparo in the Oyubari district, central
Hokkaido; location approximately 7150 m
east and 3150 m south from the northwestern corner 0. e. Lat. 43° lOIN, Long.
142°0/E) of the geological map of Oyubari(NAGAO et aI., 1954). It was embedded
solitarily without accompanied macrofossils.
This locality is situated at about the
middle of the "Santonian" sequence exposed along this stream, but whether
it is assigned to the lower part of theZone of Inoceramus (Cladoceramus?)japonicus or to the upper part of theZone of Inoceramus (Platyceramus) amakusensis is not determined on a direct
evidence. The assignment to the latterin Fig. 1 (geological map) is tentative.
Appendix

311

Notes on the Santonian
Biostratigraphy
Tatsuro MATSUMOTO
Introductory:-I have already summarized the biostratigraphic implicationsof the collignoniceratid ammonites from
Hokkaido (MATSUMOTO, 1971, p.153-156).
Here I should like to give some notesfrom the interregional standpoint on thebiostratigraphic subdivision and correlationof the Santonian primarily on the groundsof species of the Texanitinae.
The genus Texanites in a revised sense(MATSUMOTO, 1970, p. 266), including thesubgenera Texanites (s. s.) and Plesiotexanites, is widespread in various regionsof the world. Regarding the biostratigraphic implications of Texanites in the
Santonian, at least four regions should betaken into consideration.
They arewestern Europe, Madagascar, Texas andJapan.
Zonal occurrences in the four regions:From the district of Charente, southwestern France, where COQUAND (1857)
established the Santonian stage, DE GROSSOUVRE (1894) described a small specimenof Texanites texanus (ROEMER), which,
was subsequently designated by COLLIGNON (1948b, p. 42) as the type (i. e. holotype) of Texanites texanus var. gallica
COLLIGNON, and also another example ofthe same species [the same variety according to COLLIGNON, 1948J from Aude,
Southern France. DE GROSSOUVRE (1901)
subdivided the type Santonian into theZone of Texanites texanus in the lower
part and the Zone of Placenticeras syrtale(ROEMER) in the upper. There is in France
an attempt of tripartite zonation of theSantonian, with the Zone of Muniericeras lapparenti at the middle (see POMEROL,
1975, p. 247), but this does not seem to
be based on sound grounds of the data in

312

Tatsuro MATSUMOTO and Yoshi1nitsu HARAGUCHI

the type sequence. Muniericeras is restricted to the Upper Santonian in the wellstudied sequence of Madagascar (COLLIGNON, 1966, p. 96).
In the Wessex-Paris Basin Texanites
seems to be still rarer and T. cf. texanus
was listed as a very rare species from theCoranguinum Zone of Kent (WRIGHT and
WRIGHT, 1951, p. 30).
In the Munster Basin of Germany Texanites pseudotexanus (DE GROSSOUVRE)(1894) and T. (P.) schlueteri MATSUMOTO(1970) are known, but they are based on
SCHLUTER'S old collections from the shaftsin the Emscher Mergel, and it seems difficult to allocate them precisely in the
up-to-date biostratigraphic sequence (letterfrom Dr. SEITZ).
Owing to the admirable works of
COLLIGNON (1948a, b; 1966) and BESAIRIE
and COLLIGNON (1972), the Texanitinae
are best studied both palaeontologicallyand biostratigraphically in Madagascar,
where species of Texanites occur in threezones of the Santonian as follows:(1) Lower Santonian Zone of Texanites
oliveti (BLANCKENHORN), from which T.
texanus gallicus, T. texanus hispanicus
COLLIGNON and T. cf. roemeri (LAsSWITZ) are also recorded.
(2) Middle Santonian: Zone of Texanites
hourcqui, in which T. hourcqlli var.
sow'omarayensis COLLIGNON, T. oliveti
var. spinosa COLLIGNON, T. texanus gallicus. T. rarecostatus COLLIGNON, T.
quadrangulatus COLLIGNON, T. venustus
COLLIGNON, T. soutoni (BAILY), T. aff.
quinquenodosus (REDTENBACHER) and T.
(Plesiotexanites) stangeri (BAILY), including var. densicosta SPATH and var.
sparsicosta SPATH, also occur.
(3) Upper Santonian: Zone of Pseudoschloenbachia umbulazi (BAIL Y), in which
T. dichotomus COLLIGEON, T. mikobokensis COLLIGNON, T. ralijaonai COLLIGNON are characteristic and also T. quadr-

angulatlls, T. texanus gallicus, T. texanus
hispanicus, T. hourcqui var. souromarayensis, T. pseudotexanus, T. quinquenodosus and T. (P.) stangeri var. densicosta
are reported to occur.
The list may give some question about
the taxonomy and nomenclature of certain
taxa, which will be discussed in later
pages.
In Texas, where the type-locality ofTexanites texanus is located, YOUNG (1963)
has accomplished another admirable work,
showing a scheme of zonation for the
Santonian of Texas and also a range chartof selected species, in addition to the fullpalaeontological descriptions. YOUNG has
subdivided the Santonian of Texas as follows, without using the term Middle Santonian.
Lower Santonian(1) Zone of Texanites stangeri densicostus(2) Zone of Texanites texanus texanus(3) Zone of Texanites texanus gallicus
Upper Santonian(4) Zone of Texanites shiloensis YOUNG
The last species occurs, according to
YOUNG (1963, p. 90), abundantly in thelower part of the Dessau Limestone ofAustin Group. It ranges upward into thelower part of the Zone of Submortoniceras
tequestiquense YOUNG, which is assigned
to the lower part of the Lower Campanian.
From the same zone Texanites roemeri(Y ABE and SHIMIZU) and probably also
Texanites lonsdalei are recorded. These
two species show characters which suggest a close affinity with Submortonicems.
Another diagnostic species, Texanites
americanlls (LASSWITZ) typically occurs
with Inocemmus (Cladoceramus) undulatoplicatus ROEMER in the lower half of
the Santonian, but seems to extend upward to the top of unit C of the Austin
Group (YOUNG, 1963, p. 84).
In Japan the available records (MATSU-

689.

A New Texanitine Ammonite !1'om Hokkaido

MOTTO and UEDA, 1962; MATSUMOTO,
1970 ; TANAKA and TERAOKA, 1973 andthis paper) of species of Texanites andProtexanites may be summarized into threeparts as follows:(1) Lower part of the Santonian equivalent, i. e. the Lower half of theZone of Inoceramus (Platyceramus)
amakusensis: Texanites oliveti wasfound here at the type locality of I.
(P.) amakusensis in Amakusa, western
Kyushu. In Hokkaido this species has
not yet been confirmed, but Texanites
aff. quinquenodosus and Protexanites(Protexanites) bontanti shimizui MATSUMOTO occur in this part.
(2) Middle part, i. e. the upper part of
the Zone of Inoceramus (Platyceramus)
amakusensis and the lower part of theZone of Inoceramus (Cladoceramus ?)japonicus: Texanites (Plesiotexanites)
kawasakii (KA WADA), T. (P.) pacificus
and Protexanites (Anatexanites) Jukazawai (Y ABE and SHIMIZU) seem tocharacterize this part. Texanites yazakii sp. nov. is probably referred tothis part.
(3) Upper part, i. e. the upper part of theZone of Inoceramus (Cladoceramus ?)japonicus: Texanites d. shiloensis isprobably from this part. Its occurrencein the Zone of Inoceramus (Sphenoceramus) orientalis SOKOLOW, lower
part of the Campanian, has recently
been confirmed in Koshiki-jima, western Kyushu.
There are a few other species whose
stratigraphic positions are not precisely
known but somewhere in the Santonian
equivalent in Japan. They are T. (P.)
sanushibense (Y ABE and SHIMIZU) and T.
(P.) yezoensis MATSUMOTO. The last species seems to occur rather in the upper
half, i. e. the Zone of Inoc. (Cladoc. ?) japonicus, although its precise range is yet tobe worked out.

313

Towards the interregional correlation:Aside from the regions where a few
texanitine species are known without records of successive occurrence, there issome difficulty in the zonal correlation of
the Santonian between any two of theabove mentioned better studied four regions. The difficulty comes from (1) thatthe widespread species which occur commonly between two regions are often
rather long-ranging, as exemplified by T.
texanus, T. quinquenodosus and T. (P.)
stangeri; (2) that the zones are rather
of provincial subdivisions defined on thebasis of biostratigraphic records in respective regions, as best exemplified by
YOUNG'S (1963) work in the Gulf Coast
province; and (3) that some of the characteristic species of a zon'~ have a restricted geographical distribution and have notyet or scarcely been found from otherregions, for instance, T. hourcqui, T.
mikobokensis, T. ralijaonai, T. quadrangulatus and T. dichotomus in Madagascar,
T. americanus in Texas, and T. (P.) Iwwasakii, T. (P.) pacificus, T. (T.) yazalzii andProtexanites (Anatexanites) Julwzawai in
the Japanese province.
In connexion with these points the problem of speciation and phyletic evolution
in Texanites and related genera should beworked out. Our present knowledge is
not satisfactory for these requirements.
Texanites texanus (ROEMER), for instance,
was subdivided into "varieties" by COLLIGNON (1948a, b) with the implication ofgeographic subspecies: T. texanus texanus
in Texas, T. texanus gallicus in France
and other circum-Alpine area, and T. texanus hispanicus in Spain. Although COLLIGNON (1966) subsequently regarded them as
distinct species, YOUNG (1973) has kept
COLLIGNON'S earlier intention and has
added T. texanus twiningi from TransPecos Texas. I should like to admit thissubspecific separation as reasonable, if it314

Tatsuro MATSUMOTO and Yoshimitsu HARAGUCHI

could fit the facts in the nature. Actually
the extent of variation has not yet beenso satisfactorily studied to make clear
the relations of the nominal subspecies.
It is difficult for me to understand themeaning of the fact that T. texanus galieus
and T. texanus hispanieus both occur in
Madagascar and are recorded from anyof the three zones. In Texas T. texanus
galieus does occur but in a zone abovethat of T. texanus texanus. Does thismean that the French subspecies migrated
back to Texas in a delayed geologicalage? Or is T. texanus galieus a "chronological subspecies" of T. texanus texanus?
In the latter case did T. texanus galieus
migrate to France, Madagascar and otherregions in that delayed age? The reason
why the lower three zones in Texas wereassigned to the Lower Santonian was that
T. texanus gallieus, the same subspecies
as the index of the Lower Santonian inFrance, characterizes the third zone
(YOUNG. 1963, table 7). In view of thelong range of T. texanus gallieus, as
shown in Madagascar, such a reasoning
would not necessarily be maintained in
the interregional correlation. Thus, it
seems me difficult to conclude an interregional correlation in such a fine scaleby means of the hitherto known subspecies of T. texanus and furthermore, eventhe adequacy of this subspecific separation
may become doubtful. Should we follow
COLLIGNON'S later interpretation of specific distinction, the separated species
would be said useless for the correlation
in a fine scale. It would be desirable toreexamine the true state through the concept of population palaeontology.
The hitherto admitted subspecies within
Texanites (Plesiotexanites) stangeri (BAILY)
is likewise meaningless, although SPATH'S(1922) variety names densieosta and sparsicosta may be convenient to express certain
forms in the variation of that species.

Be that as it may, T. (P.) stangeri is
widespread, being found even in Hokkaido,
but seems to have a long vertical true
range, since it is recorded to characterize
the lower part of the Lower Santonianin Texas and to occur in the Middle andUpper Santonian of Madagascar. Thus,in the world scale the well known species
T. texanus and T. (P.) stangeri canonly indicate the Santonian stage and do
not seem to be suitable for finer correlation.
Texanites (T.) oliveti seems to be a better index species, for it occurs in a comparatively lower part of the Santonian inboth Madagascar and Japan. By courtesyof Dr. W. A. COBBAN I saw once a probable example of Texanites oliveti in thecollection of the United States Geological
Survey at Denver, which came from loco
USGS. 1467 in western Texas. As it isassociated with Clioseaphites vermiformis(MEEK and HAYDEN), it records the occurrence of this species in the lower part of
the Santonian in North America.
Texanites oliveti in the above discussion
is in the sense of redefinition by COLLIGNON (1948a, p. 72). Whether this is truly
identical with the original of Mortonieeras
oliveti BLANCK EN HORN (1905) or not may
be a question, since the type specimen
from the Middle East is secondarily muchcompressed. Furthermore, whether T.
oliveti (of a larger size) from the Middle
East is specifically well distinguished fromT. quinquenodosus (of smaller sizes) may
be another problem. In the Middle East,according to Dr. Z. LEWY (1977, personal
information), Texanites sp. of the quinquenodosus subgroups occurs in the Lower
Santonian closely associated with Spinaptyehus spinosus. Whether T. oliveti var.
spinosa COLLIGNON is a mere variant orhas· a meaning of the so-called chronological subspecies should also be reexamined.

689.

A New Texanitine Ammonite from Ho7c7caido

Texanites (Plesiotexanites)
shiloensis
seems to be another good index of theUpper Santonian plus basal Campanian,because its occurence in Texas and Japan
show a good correspondence. Certain
associated species can tell the discrimination of the Upper Santonian from theLower Campanian.
Despite a number of difficulties, I dare
attempt to set forth a tentative schemeof a tripartite subdivision of the Santonian by ammonites as a step towards
future refinement. The three zones in
Madagascar are tentatively correlated withthe tripartite units in Japan; the fourthzone in Texas with the upper unit inJapan; the second and the third zones in
Texas are assumed to be approximately
correlated with the Middle Santonian in
Madagascar (and in Japan). When we
admit this scheme, how the three parts
are correlated respectively with whatparts of the Santonian in France andother areas of western Europe is a keen
problem. Anyhow, on the ground of thisprovisional correlation, a tentative rangechart of some selected species of the
Texanitinae is shown in Fig. 3. In a
few cases the range of a species isdefinitely known by the successive occurrence of its fossils in a measured sequence. In many other cases the locality
records of a named species are scatteredsomewhere within a given unit. Even insuch a case, the species is tentatively
indicated in Fig. 3 as if it ranges
throughout the unit. When the available
records are still more uncertain, thepresumed range is indicated by a broken
line in the chart. These may be revisedin the future, if more accurate locality
records are enough assembled.
The
chart (Fig. 3) contains Texanites (Plesiotexanites) thompsoni (JONES) (see MATSUMOTO, 1970, p. 277), as an example fromthe West Coast of North America, for315

the age of which I depend on DOUGLAS(1969) who refined the record of JONES(1966). The chart may also be useful toknow the general evolutionary pattern of
Texanites species. As is shown in Fig.
3, the diverging speciation is considerable
in Texanites, whilst little has been known
about the successive phyletic evolution ofa particular lineage. The dotted line
connecting any set of two species in Fig.
3 means that the two species are described to be allied to each other, although
the actual line of descent has not yet
been traced with sufficient evidence.
There are a few long-ranging species.
Certain species of restricted distribution
may have been diverged or specialized
from a common root species simultaneously or at dissimilar times. Only a roughly
parallel similarity is found between
certain two species with respect to acertain character but they are dissimilar
in other characters. T. yazallii and T.
hourcqui may demonstrate such a case of
seemingly similar but actually differentiated or diverged species. Their presumed
contemporarity is by no means strictly
evidenced. Therefore, they should not
be too much relied upon for a precise
interregional correlation, until their wider
distribu tion be known.
Incidentally, T. hOlll'cqui has beenreported from bed 72 in the upper partof the Calendin Formation of Peru whichis assigned to the Zone of Lenticeras
baltai LrssoN (BENAVIDES-CACERAS, 1956).
The age of this zone was regarded by
the same author as early Santonian.
Presumably he must have depended on
COLLIGNON'S earlier paper (1948a, p. 79),
in which the age of T. hourcqui wasreferred to the Upper Coniacian or the
Lower Santonian. In the later works of
COLLIGNON (1966) and BESAIRlE andCOLLIGNON (1972) T. hourcqui has turned
to be a zonal index ·.of the Middle

316

Tatsuro MATSUMOTO and Yoshimits'/,~ HARAGUCHICAMPAN.

5 A N T 0 N I A N

CONIAC.

UPPER

M I DOLE

LOWER

UPPER.

T.

LOWER(T.) dicho tom us

T. (T.) venustus! T. (T.) hourcqui
T. (T.) yazakii,- :(var.)

___ 0

__ -

--

T. (T.) quadranguiatus

,
,
,,

..,,

T. (T.) mikobokensis,
Texanites (Texanites) texanus.'.'"

T. (T.) quinquenodosus(T. ) oliveti

T.

···,
··
·

(var. )··,__ 0_._-

T. (T.) rarecos ta tus

T. (T.) americanus
T. (P. ) stangeri

T. (P. ) raiijaonai
T. (Plesio texanites),, T. (P.) pacific us:,,
Protexanites

planatus

Pr. bontanti

bon tan ti

.

.

:

kawasakii

T. (P.) shiloensis"\Pr. (Anatexanites) fukazawaip;"j bontanti shimizui
T. (P. ) thompsoni--------

T. (P.) yezoensis- - - - - - - --T. soutoni

Fig. 3. Selected species of Santonian Texanitinae and their known
stratigraphic ranges in the tentative scheme of subdivision.

Santonian.
Finally I must give comments on someinoceramid species. The' well known
species Inoceramus (Cladoceramus) undulatoplicatus ROEMER is regarded as a world-

wide index of theLower Santonian
In Texas,
the type area of this species, YOUNG(1963, text-fig. 4) has clearly indicatedthat it ranges in the lower part of the(KAUFFMAN, 1975, oral comm.).

689.

A New Texanitine Ammonite from Holclcaido

Santonian, occurring in the first two zonesof Texanites. As it is distributed widelyin various regions and occurs moreabundantly than any species of Texanites,
it must be useful to check the age correlation between species of Texanites orother ammonites of scattered occurrence.
This should, however, be maintained
within the true distributional area of I.
(C.) undulatoplicatus.
Inoceramus (Cladoceramus?) japonicus
NAGAO and MATSUMOTO in a revised
sense [see MATSUMOTO and VEDA (1962,
p. 165) in which the best preserved
SASA'S specimen (forma r of NAGAO and
MATSUMOTO, 194D, pI. 9, fig. 1; MATSUMOTO and VEDA, 1962, pI. 24, fig. 1) was
designated as the lectotype] characterizes
the upper part of the Santonian correlative in Japan, while Inoceramus (Platyceramus) amakusensis is characteristic of
the lower part. Now, J. (C. ?) japonicus
is seemingly very similar to J. (C.) undulatoplicatus and some authors (e. g. STEPHENSON, 1950) considered that they could
be identical. If this was admitted, thenthe age discrepancy would be evident
in the stratigraphic occurrence of this"identical species" between the Japanese(or northwestern Pacific) and the Euramerican provinces. The associated Texanites species may demonstrate this. I
still hold the opinion of MATSUMOTO andVEDA (1962) that I. (C. ?) japonicus is not
identical with I. (C.) undulatoplicatus butthat they show a convergence in thedivergent ribbing between fairly close
but not quite identical lineages. SEITZ(1961, p. 109) seems to have the same
opinion.
In concluding the above discussions, anumber of questions has been pointed out
to be worked out in the future towards a
refined scheme of Santonian zonation andcorrelation.

317

References Cited
BENAVIDES-CACERAS, V. E. (1956) : Cretaceous
system in northern Peru. Bull. Amer.
Museum Nat. Hist., vol. 108, no. 4, p. 353494, pIs. 31-66.
BESAIRIE, H. and COLLIGNON, M. (1972) : Geologie de Madagascar 1. Les terrain sedimentaires. Ann. Ceol. Madagascar, no.
35, p. 1-,163, pIs. 1-89.
BLA="CKENIIOR:-.i, M. (1905):
Geologie dernaheren Umgebung von Jerusalem. Zeitsch.
Deutsch. Palaestina- Vereins, vol. 28, p. 75120.
COLLIG="ON, M_ (1948 a, b): Ammonites neocretacees du Menabe (Madagascar). 1.
Les Texanitidae. Ann. Ceol. Servo Mines,
no. 13, p. 49-107, pIs. 7-20 (1948a) ; Ibid.,
no. 14, p. 8-60, pIs. 15-32 (l948b).
- - (1966): Atlas des Fossiles Caracteristiquesde Madagascar (Ammonites), fasc_ U (Santonien), 134 p., pIs. 455-515.
COQUA="D, H. (1857): Position des Ostrea
columba et biaUl'iculata dans Ie groupe dela craie inferieure. Bull. Soc. Ceol. France,
2 ser., vol. 14 (1856-1857), p. 745-766.
DOUGu.s, R. G. (1969): Upper Cretaceous biostratigraphy of northern California. Proc.
1st Int. Conf. Planktonic Microfossils,
Geneva, 1967, vol. 2, 126-152.
GROSSOUVRE, A. DE (1894): Recherches surla Craie superieure. II. Paleontologie.
Les ammonites de la Craie superieure
Mhn. Carte Ceol. Det. France, 1893, p. 1264, pIs. 1-39.
- - (1901): Recherches sur la Craie superieure. 1. Stratigraphie genera Ie. Ibid.,
1901, (1), p. 1-558, (2), p. 560-1013.
JONES, D. L. (1966): New Upper Cretaceousammonite, Protexanites thompsoni, from
California. Jour. Paleont., vol. 40, p. 199203.
MATSUMOTO, T. (1942): Fundamentals in the
Cretaceous stratigraphy of Japan. Part
1. Mem. Fac. Sci., Kyushu Imp. Univ.,
ser. 0, vol. 1, p. 129-280, pIs. 5-20.
- - (1965): A monograph of the CoIIignoniceratidae from Hokkaido. Part 1. Mem.
Fac. Sci., Kyushu Univ. ser. 0, vol. 16,
no. 1, p. 1-80, pIs. 1-18.

Tatsuro MATSUMOTO and Yoshimitsu HARACUCHI

318(1970): Ditto. Part IV. Ibid., vol. 20,
no. 2, p. 225-304, pis. 30-47.
- - (1971): Ditto. Part V. Ibid., vol. 21,
no. 1, p. 129-162, pis. 21-24.
- - and UEDA, Y. (1962); Paleontologicalnotes in UEDA, Y. (1962): The type Hi·
menoura Group. Ibid., vol. 12, no. 2, p.
161-174, pis. 22-27.
NAGAo, S., OSAi\AI, H. and SAKO, S. (1954) :Oyubari. Expl. Text. Ceol. Map japan,
scale 1; 50,000, p. 1-12, pis. 1-9, 1 map,
Hokkaido Development Agency, Sapporo.
NODA, M. and MATSUMOTO, T. (1976) : Meso·
zoic bivalves from Japan, 4 (Inocerami).
Atlas of japanese Fossils, no. 4;:;, 24p. incl.
6pls., Tsukiji Shokan, Tokyo.
POMEROL, Ch. (1975): Stratigraphie et Paleo·
geographie. Ere Mesozoique, 383p., doin,
Paris.
SEITZ, O. (1961); Die Inoceramen des Santon
von Nordwestdeutschland. 1. Teil. Beih.

Ceol. jahrb., no. 46, p. 1-186, pis. 1-15.
SPATH, L. F. (1922): On the Senonian am·
monite fauna of Pondoland. Trans. Roy.
Soc. S. Africa, vol. 10, pt. 3, p. 118-147.
STEPHE);SON, L. W. (1950); Index fossils withparticular reference to the Upper Cre·taceous of eastern United States. jour.
Ceol. Soc. japan, vol. 56, p. 89-94.
T Ai\AKA, K. and TERAOKA, Y. (1973) : Strati·
graphy and sedimentation of the Upper
Cretaceous Himenoura Group in Koshiki·jima, southwestern Kyushu. Report Ceol.
Surv. japan, vol. 24, p. 157-18cl, pis. 15-24.
YOUNG, K. (1963): Upper Cretaceous ammo·
nites from the Gulf Coast of the UnitedStates. Univ. Texas Publ., no. 630cl, p. 1373, incl. 82pls.
WRIGHT, C. W. and WRIGHT, E. V. (1951): A
survey of the fossil Cephalopoda of the
Chalk of Great Britain. Palaeontogr. Soc.,
1951, p. 1-40.

Agemaki-zawa C=Kamimaki.zawaJ (J-3~1R), Amakusa (:RJii) , Haboro (~~IPJf,), Komaki·
zawa (/J',{!:IR) ,Kosen·zawa (~+lUR),
Koshiki.jima (i'l1I,i1l,) ,Kotambetsu (ilftSU),Obira (/J':ijZ) ,Omaki·zawa (j;:~IR),
Oyubari (*9iJft) ,Panke-horoka·yuparo (/~ :/?"
;J-< P 7J ;;:!. - /~ p),
Panke·mo·yuparo (/~ :/?" '1:::;:J. - /~ p),
Penke·horoka·yuparo (A.:/?";J-< P
7J;;:!. /~ p),
Shimizu·zawa (lI'f7.KlR) ,Shiyubari [=Shiyuparo, Shuparo, Shuyubari] (-/:;:J.-/~ D,I),-/:;:J.-/~ P,-/ "- -/~ P,±'9~)[71 ;;<~~lR<1)Jtlri6>a:-'f1].i511::L-tc.J~-€f<1)lJfU:JJ~i)d;:J::i tc.J~fn;: J:: I; ~ tJ: ~ J~tWJgil€<1)~ L- \" T 4'- -l)-j" 1 T A; ~t$JgJ:flIlB]I!i:*il€<1) Texanitinae (Collignonicer.
atidae H<1)cp<1) 1 ill!H) ~;:~-t ~ 7 :/'1:: j" 1 Hi, MATSDIOTO (1970) <1) '1:: / p' '77 i;:&Jii\i:-n, ~ iJ~, 1&:iIi*951UtlJ.:JJ>a:-}1!2jf{WI.]ftl=!,i;:, 1tt*§clf~~:h'n, tJ: \" T 4'- -+rj" 1 T A >a:-1*:tR
L- tc.o ;: ;h,~i '" 31" 7f A 7J Iv il€<1) Texanites hourcqui iC, IDtJf3 C}lj]<1)tiilA ~n\.ll&:iJ~J1\1:if-II~j i "'C'
;5 ~ ,~tJ: C- iJ:fJJ -n, ~ iJ~, ~i@<1) i'iC7U<1) rJ39Pi\\i~*1tMJR<1) L <1)tt:lJUJ: D;: I1)j ii'!I1tJ:il§:~iJ~;5 I),!f!f~tJ: 1 ~fffi>a:-f\;;~-t~ c;;z,.tJ:~;h,~<1)-C" ;: ;:1;:§cJii\i:-t~o il€iliffi'il:t-l)-:/ I- =-7 AIH13fl1lO)
I:!:I!cp~:l: c'-C';5 I), am>a:-t.1..., tc.~~*:lN<1)11::15 iJ~, .!ti\(s9r91 -€f;f§<1) tJE:E-i;:l7Jlft L- -c.,il€ Uc.;:~;h,ct~~~;5~o~fH*:lli*~M·.c.~;:<1)f,,'l!:~I;:,

H<1)'fjf[>a:-<j"{" c L- -C,-l)-:/ I- =-7 :/<1)11::::E@Jf~B91K7tU;fl:U;:")\"-C, T4'--l)-j"11-ill!

~~(1<].w.:tmiJd? <1)~tniID!>a:-ili\;z,. ~ 0t~*~fl~Explanation of Plate 42
Figs. 1-2. Texanites yazalcii sp. nov .................................................. Page 307
Holotype, GK. H5865, from loc. Y1l20, collected by Y. HARAGUCHl.
1. Lateral (a), ventral (b) and frontal (c) views of the inner whorls, xl.
2. Lateral view of the entire specimen, excluding the deformed last part, x 0.5.
Kyushu University (K. TANABE) photos without whitening.

M A TSUMOTO

and H A RAG UC HI ,' Te xanites

Plate 42Trans. Proc. Palaeont. Soc. Japan, N. S., No. llO, pp. 319-329, pis. 43, 44, June 30, 1978

690.

ON SOME INTERESTING EIV AL YES FROM THE CRETACEOUS
HIMENOURA GROUP IN KYUSHUMASA YUKI T ASHIRO*
Shokei Highschool, Kumamoto 862

Abstract. Here are described three new species and one new subspecies of thebivalves from the Santonian of the Himenoura Group in an area of Amakusa-Kamishima in Kyushu. Atreta intulaevis sp. nov. is characterized by a single adductor
scar. Accordingly Atreta can undoubtedly be classified into the Plicatulidae as
already suggested by Cox (196-1). Since Pycnodonte and Thyasira prospered in Africa,
Europe and N. America from the Campanian onward, Pycnodonte a11lakusensis sp.
nov. and Thyasira (Thyasira) hi11ledoensis sp. nov. from the Santonian were probably
among the older forms in each genus. Chlamys (s.l.) tamurai tamurai and Chla11lYs(s. 1.) ta11lurai im11lodesta subsp. nov. are characterized not only by the surface
ornamentation of Mesozoic pectinids, e. g., Camptonectes and Camptochlamys, butalso by that of Cenozoic ones, e. g., Palliolu11l and Eburneopecten.

Introduction and Acknowledgements
This paper treats the description of
three new species and one new subspeciesof Cretaceous bivalves under the genera
Atreta, Pycnodonte, Thyasira and Chlamys,i. e. Atreta intlilaevis sp. nov., Pycnodonte
amakllSellsis sp. nov., Thyasira (Thyasira)himedoensis sp. nov. and Chlamys (s.1.)
tamurai immodesta subsp. nov. from theLower Formation of the Lower Himenoura
Subgroup of the Himenoura Group in
Amakusa-Kamishima island in Kumamoto
Prefecture.
The species of Atreta, Pycnodonte andThyasira in this paper may be the firstrecord from the Japanese Mesozoic. Chlamys ta17l11rai tamurai and Chlamys tamurai
immodesta have very interesting sculptureon the surface for members of the genus

Chlamys or the allied genera.
Before going into the description, I wish
to express my sincere thanks to Professor
Minoru TAMURA of Kumamoto University,
for his kind encouragement and reading. of this manuscript. I also thank to Dr.
Ikuwo OBATA of the National Science Museum of Tokyo and Dr. Yasumitsu KANIEof the Yokosuka City Museum for supplying me many specimens of Pycnodontefrom the Cretaceous of Madagascar. I
am grateful to Mr. Tatsuya MATSUMOTO,
a student of Tokai University, for supplying me some recent specimens of Thyasiraand Palliolum.

Description of species

Family Pectinidae RAFINESQUE
Genus Chlamys RODlNG, 1778

Received Septem.ber 19, 1977; read Oct. -I,
1976 at Sapporo* Present address: Institute of Geology,
Kochi University, Kochi 780.

Chlamys (s.1.) tamllrai T ASHlRO, 1976

319

Masayuki TASHIRO

320

Chlamys (5.1.) tamurai immodesta,

subsp. nov.
Plate 43, Figs. 1-4, Text-fig. 2

j\!/aterial :-The holotype (KE 2751) isan external mould of a right valve collected from the Lower Formation of theLower Himenoura Subgroup at Hinoshima island of Amakusa-Kamishima,
Kumamoto Prefecture. The para types(KE 2752-KE 2757) were collected fromthe same locality. Another para type (KE2758) is an external mould of left valve
collected from the same formation at
Takagushi of Ryugadake-machi, AmakusaKamishima, Kumamoto Prefecture.
Description :-Shell roundly ovate, nearly equilateral, inequivalve, weakly inflated,somewhat higher than long; hinge line
straight, occupying about a half of thevalve length; anterior and posterior
margins nearly straight; ventral marginsemi-circular; umbo small, improminent,
located nearly mid-point of valve length;
apical angle about 75°; anterior ear

larger than posterior, vertically truncatedin left valve, forming a byssal notch inright; posterior ear obliquely truncated;
external surface ornamented with two
sorts of ribs except for fine crowded
growth lines; one is primary and secondary radial ribs, which are narrower thantheir interspaces, finely spinose on ventral
part, stronger and more numerous in left
valve than in right, crowded and strong
on anterior and posterior parts of thedisk; the ribs counted about 70 in total
number on left valve, and about 30 primaries and a little developed secondaries
on anterior and posterior ventral parts ofright valve; the secondary ribs of left
valve beginning to appear at about 20
mm from umbo; the other sort of ribs
very fine and numerous, divaricate,numbering about 10 within a distance of
5 mm on ventral margin in a mature
specimen, and developed on marginal
part of valve; ears ornamented in thesame way as the disk; two pairs ofcardinal crurae on hinge area; one pairon both sides of resilifer short; the otherText-fig. 1: Map showing fossil localities
B: Bozujima islet H: Hinoshima island K: Kugushima islet T: Takagushi W;
Wadanohana a: Atreta intulaevis, sp. nov., Pycnodonte amakusensis, sp. nov. andChlamys (s.l.) tamurai immodesta, subsp. nov. b: Thyasira (Thyasira) himedoensis,
sp. nov. c: Chlamys (s.l.) tamurai immodesta, subsp. nov.

690.

On Some Interesting Bivalves321

pair below hinge line elongated, parallel
to cardina l axis; inner surface smooth;
adductor scars indistinct ; inner marginsmooth.

N/ easul'ements (in mm):Specime n
KE 2751, ri g ht ex . mould
KE 2752, left e x . mould
KE 2753 , ditto
KE 2754, ditto
KE 2755, ditto
KE 2756, le ft in. mould
KE 2757, ri g ht valve
KE 2758, left e x . mould

Length24 . 5
26. 7
18.5
24. 1
16. 8 +
26 .5
18.0
39 . 5

He ight
26. 1
28. S+
21. 2+
25 . 9+26 . 330.4
19.5
40. 1 +

R emal'/ls :- This subspecies is discriminated from Chlamy s (s. 1.) tamul'ai
tamumi from the Upper Campanianstage of the Himenoura Group and theIzumi Group in hav ing the ill-deve lo ped
diverging ribs on the main part of thedisk, which are well developed only nea r
ventral margin, and a lso in havi ng mOrE:
or less receded secondary radial ribs.
The generic position of these two subspecies, tamumi and immodesta is uncertain, although they are tentatively
placed in Chlamys (s.1.) in this paper.
They are different from hitherto described
species of Camptonectes, Camptochlamys
and Chlamys in followings features: suchspinose radial ribs are unknown in any
species of Camptonecte s and Camptochlamys, such divaricate ribs do notappear in any species of Camptochlamys
and Chlamys, and that the radial ribs
are much stronger and more regu larly
spaced in the species of Chlamys. Some
species . of Ebumeopecten from the Tertiary are similar to these forms in having
two sorts of ribs (radial and di varicate).
The two sorts of ribs in the species of
Ebul'neopecten, however, are very fineand microscopic. And the species of
Ebumeopecten lack spines on the radialribs. Micl'onectes bellaturus ICHIKAWA

Text-fig. 2. A : Chlamys ( 5.1. ) tamurai
tamllrai T A S HIR O , right va l ve B: Chlamys(5. 1. ) tamllrai immodesta, subsp. no v . rightva lve.

and MAEDA (1958; Eburneop ecten (Micronectes) bellalurus (ICHIKAwA and MAEDA) :HERTLEI , 1969) from the Upper Cretaceous Izumi Group in Shikoku has a lso two
sorts of ribs but differs from these forms
in having the distinct concentric ribs or
bundles which are widely spaced on thedisk, and the more inflated and smaller
shell than in these forms. The Recent
species of Palliolum, P. striatum (MULLER)

322

Masayuki T ASH! RO(ABBOTT, 1955) and P. macrocheiricola
HABE (1951) are closely similar to these
two subspecies in the fine diverging
ribs and spiny radial ribs on the disk.
These subspecies, however, are muchlarger in size than the species of
Palliolum.
HERTLEIN (1969) classified the generaof the Pectinidae into nine groups. In so
far as I can see, these subspecies, tamurai
and immodesta, belong to none of hisgroups, although they have some characteristic similar to the Camptonectes
group, Eburneopecten group or Chlamys
group. A new generic name may be required for these two subspecies, tamurai
and immodesta.
Occurreilce :-Siltstone or fine sandstoneof the lower member of the Lower Formation of the Lower Himenoura Subgroup at the roadside exposure of northwest beach of Hinoshima island, Ryugadake-machi, Amakusa-gun, Kumamoto
Prefecture. Siltstone of the same member at the seashore of Takagushi of
Ryugadake-machi, Amakusa-gun, KumaMiddle Urakawan
moto Prefecture.
(Lower Santonian): Inoceramus amakusensis Zone.
Family Plicatulidae WATSON
Genus Atreta ETALLON, 1862
Atreta intulaevis, sp. nov.
Plate 44, Figs. 1-4, Text-fig. 3

Material :-The holotype (KE 2759) isan internal mould of right valve collectedfrom the Lower Formation of the Lower
Himenoura Subgroup at Hinoshima island,
Amakusa-Kamishima, Kumamoto Prefecture.
The paratypes (KE 2760-KE
2764) were collected from the same
locality.
Description :-Shell roundly subquadrate,
slightly inflated, hinge line straight, about

a half length of valve; umbo very small,located at about three-sevenths of lengthfrom front of valve; anterior margin subvertical near hinge margin but graduallyarched on anterior ventral part; ventral
margin well rounded; posterior margin
obliquely subtruncated; postero-ventral
part semi-circularly rounded; ligamentarea narrowly triangular, short and about
one nineth of valve length; ligamentgroove very narrow, vertically set fromumbo to central point of hinge line;
internal surface of right valve divided
into bowl-shaped shallow central partand ring-shaped flat marginal part by anelliptical and crenulated rim; central part
ornamented with fine radial striae which
are restricted near elliptical rim; striae
very often weakened or disappeared insome specimens; an orbicular and elongated adductor scar indistinctly impressedon a little posterior area in central part;
resilifer and two pairs of crurae present
near mid-point of hinge; resilifer verysmall, triangular, located under umbo,
connected with ligament groove on thetop; a pair of crurae long, crenulated
and obliquely extended from umbo toeach anoterior and posterior margin;
another pair of crurae short and verysmall, occupied radially on both lateralsides of resilifer; ventral margin smooth;
external surface of left valve ornamented
with fine concentric riblets; externalsurface of right valve unknown.
Measurements (in mm):Specimen
KE 2759, right in. mould
KE 2760, ditto
KE 2761, ditto
KE 2762, ditto
KE 2763, left ex. mould
KE 2764, ditto

Length
17.7
14.5
21. 9
10.0
12.0
10.0

Height
16.4
13.0
18.6
9.8
1l.5
9.0

Remarks:-This species occurs commonly on the surface of Inoceramus
amakusensis NAGAO and MATSUMOTO

690.

On Some InteTesting Bivalves

B

Text-fig. ;): Atreta intulaevis, sp. noy.
A: internal view of right valve, showing
the specimen with weak internal radialstriae. B: li:;amental view of right valve.

(1940), and rarely on the surface ofChlamys (s.l.) tamurai immodesta, subsp.
nov.. Fine parallel striae appear on the
inner surface of right valve in several
specimens of this species (PI. 2, fig. 3).
The striae may be influenced by thegrowth line of the specimen of Inoceramus
amakusensis to which the individual
adheres. This species resembles the typespecies of Dimyodon, D. schlumbergeri
MUNIER-CHADIAS (Cox and HERTLEIN,1969) from the Bathonian of Europe, andDimya, D. deshayesiana RONAULT (ZITTEL,
1924, Cox and HERTLEIN, 1969) from the
Eocene of France, in having crenulated
rim and the hinge structure, but differsfrom the two foreign species in thenumber of adductor scars, which are twoin those European species and one in thepresent species. Cox (1964) discriminated
Atreta from the Dimyidae, which includes
Dimyodon and Dimya by the number of
adductor scars, because he was not able
to detect the two adductor scars in thespecies belonging to Atreta. And he323

placed Atreta into the Plicatulidae. As
one large adductor scar is faintly impressed on the inner surface, this species
undoubtedly belongs to the Plicatulidae.
Comparison :-Atreta blandina (D'ORBIGl\'Y) (emend Cox, 1964) from the Oxfordian of France is similar to this species
in the sub quadrate outline of right valve,
but differs from this species in having
distinct radial or divaricating striae on
the internal surface. This species is discriminated from Atreta nilssoni (HAGENOW) (Plicatula sigillina WOODWARD by
WOODS, 1901) from the Lower Cretaceousof England by the nearly smooth innersurface. Atreta cretacea (CONRAD) (Diploschiza cretacea CONRAD: WHITFIELD, 1885)
from the Upper Cretaceous of North
America resembles this form in theorbicularly subquadrate outline, but differs from this species in the more strongly
inflated left valve. Atreta chavani (COLLIGNON) (Diploschiza chavani COLLIGNON,
1951) from the Uppermost Cretaceous ofMadagascar clearly differs from thisspecies in the distinct internal divaricating
riblets.
Occurrence :-Black siltstone of the lower member of the Lower Formation of
the Lower Himenoura Subgroup at theroadside exposure of northwest beach of
Hinoshima island of Ryugadake-machi,
Amakusa-gun, Kumamoto Prefecture. Middle Urakawan (Lower Santonian): Inoceramus amakusensis Zone.

Family Gryphaeidae VYALOV
Subfamily Pycnodonteinae
STENZEL, 1959
Genus Pycnodonte FISCHER
de W ALDHEIM, 1835
Pycnodonte amakusensis" sp. nov.

324

Masayuki TASHIRO

Plate 43, Fig. 9, Plate 44, Figs. 5-11,
Text-fig. 4

Material :-The holotype eKE 2765) isan internal mould of left valve from theLower Formation of the Lower Himenoura
Subgroup at Hinoshima island, AmakusaKamishima, Kumamoto Prefecture. The
para types eKE 2766-KE 2769) are internalmoulds of left valve, the para type (KE2770) external mould of left valve, andthe paratypes eKE 2771-KE 2772) externalmoulds of right valve. All the paratypes
were collected from the type locality.
Description :-Shell inequilateral, highly
inequivalve :Right valve :-Shell roundly subquadlate,slightly inflated; anterior and posterior
margins nearly straight near umbo but
rounded on both lateral sides; anterior
margin subvertical; ventral margin broadly arched; posterior margin obliquely
subtruncated; umbo small, improminent,
strongly opisthogyrous, located near the
mid-point of valve length; surface orna-

mented with fine radial striae and widely
spaced and irregularly waved growthlines.
Left valve :-Shell orbicular in outline;
hinge margin straight, occupying about
a half length of valve; anterior margin
truncated, nearly vertical, gradually changing into broadly arched ventral margin;posterior margin obliquely truncated;postero-ventral margin well rounded;umbo small, improminent in younger
stage, strongly opisthogyrous, located near
the mid-point of valve length, and at
about three-fifths from the anterior endof hinge margin; ligament area narrow,elongatedly triangular; ligament groove
obliquely extended from umbo to central
point of hinge line; internal surface
divided into bowl-shaped shallow central
part and ring-shaped flat marginal partby an elliptical rim; central part nearlysmooth except for several blunt concentricwrinkles and a large orbicular adductor
scar; numerous tooth-like chomata arranged on both sides of rim under hinge

Text-fig. 4: Pycnodonte amakusensis, sp. nov.
A: internal view of left valve. B: ligamental viewof left valve. C: external view of right valve.

690.

On Some Interesting J3ivalvesline; external surface unknown in younger
stage; a strong sulcus running from umbo
to postero-ventral margin; surface nearlysmooth except for irregularly waved
growth striae.
l\;feasurements (in mm):Specimen
KE 2765, left in. mould
KE 2766, ditto
KE 2767, ditto
KE 2768, ditto
KE 2769, ditto
KE 2770, left ex. mould
KE 2771, right ex. mould
KE 2772, ditto

Length
16.0
13.2
14.2
29.2
9.0
28.3
23.3
29.9

325

Family Thyasiridae DALL
Genus Thyasira LEACH in
LAMARCK, 1818
Thyasira (Thyasira) hi711edoensis, sp. nov.
Plate 43, Figs. 6-8, Text-fig. 5

Height
17.8
11. 5
16.5
20.1+
9.2
28.3
25.8
28.2+

Remarks:- The internal surface of rightvalve is unknown. The umbonal part ofleft valve generally attaches itself to thesurface of Inoceramus amalwsensis NAGAO
and MATSUMOTO. The convexity of left
valve becomes stronger through thegrowth. The radial striae on the externalsurface of right valve number about 15
on the ventral margin.
Comparison :-This is similar to the immature stage of Pycnodonte vesicularis(LAMARCK) (WHITFIELD, 1885; FRENIEX,
1972) from the Upper Cretaceous of North
America, Europe and Africa, in the elongated hinge margin and the rounded outline, but differ from P. vesicularis in thestrongly opisthogylate umbo. Pycnodonte
subhippodium (D' ARCHIAC) (STENZEL, 1959,
1971 ; Ostrea (Biauris) subhippodium: CosSSMANN, 1922) from the Eocene of France
also differs from this species in the orthogyrous umbo.
Occurrence :-Black siltstone of the lower member of the Lower Formation of
the Lower Himenoura Subgroup at theroadside exposure of northwest beach of
Hinoshima island of Ryugadake-machi,
Amakusa-gun, Kumamoto
Prefecture.
Middle Urakawan (Lower Santonian):
Inoceramus amakusensis Zone.

1976. Thyasira sp. T ASIIIRO, Pa/aeont. Soc.
Japan, Sp. Pap., no. 19, p. 61, pI. 9, fig. 6.

Material-The holotype (KE 2165) isan internal mould of left valve. The
paratypes (KE 2773-KE 2774) are deformed
right valve and a conjoined specimen.
These type specimens were collected fromthe Lower Formation of the Lower Himenoura Subgroup at Kugushima islet, Amakusa-Kamishima, Kumamoto Prefecture.
Description :-Shell orbicular, moderately inflated, much taller than long; beaksmall, curving inward; umbo prosogyrous,
moderately inflated, located at a little
anterior to mid-point of valve-length;
umbonal angle about 80° ; anterior dorsal
margin slightly concave; anterior margin
weakly arched and gradually changing
into well rounded ventral margin; anteroventral part slightly sinuated; posterior
margin moderately arched; postero-ventral
part weakly concave; posterior dorsal
margin not demarcated clearly from posterior margin; surface marked with fine,closely and irregularly spaced growthlines; anterior sulcus broad, very shallow,
extending from umbo to anterior ventral
margin; a broad but prominent primarysulcus extending from umbo to posteroventral margin along postero-dorsal slopeof rounded umbonal ridge; a ridge
nearly straight; submarginal sulcus orposterior sulcus very shallow, situatedjust below posterior dorsal margin; a foldbetween primary sulcus and submarginal
sulcus slightly convex; lunule distinct,
bounded by well defined low ridge; ligament groove gently curved, elongated,326

Jl!IasaY~ilci T ASH J RO

extending from behind umbo to posterior
end of posterior dorsal margin; hinge
teeth indistinct; internal surface ornamented with nume rous and fine radialstriae.

Measurements (in mm ) ;Specime n
KE 2165, left va I ve
KE 2773, ri g ht va lve
KE 2774, conjoint va lve

Text-fig. 5 : Thyasira(Thy asira)himedoensis, sp. As .: ante rior sulcus Ps: primarysulcus Ss : poste rior sulcus or sub ma rg in a lsulcus.

Le ngt h
14. 0
27.5
31. 2

I-l e ig ht
IS.6
33.6
35 . 1R emarl,s ;- This species occurs ve ry
rarel y, a nd generally in broken or deformed states. As the surface ornamentation and the shell structure of the valve
are we ll prese rved in severa l specimens,
the specific characters of this species areable to be described. Cretaceous Thyasira
inves ti gated in detail by K AU FF iVIAN (1976).
Acco rding to him, Cretaceous T hyasirafrom the Western Interior of North A merica is classified into 7 species and 10
subspec ies. They occur fro m the Campa-

Explanation of Plate 43
F igs. 1-4. Chlamys (s. I. ) tamurai im modesla, subsp. nov.
la : rub be r cas t of e xte rna l mould, ri ght valve holo type (KE 2751 ) , x 1.2, Loc. roadsid e
exposure of northwe st beach of Hinoshima is land, Amak usa -K amishima, Ku mamo to Pre fe cture .
Ib: same specime n , x 2
2 : r ubbe r cast of e x terna l mo uld , left va lve, parat ype (KE 275S) , x l, Loc. e ast e rn
se ashore of Ta kag ushi of Ryugada ke-machi, A m akusa-Kamis hima , Kuma mo to Prefecture .
3 : inte rna l mould of left va lve, para type (KE 2756) , x 1.2, Loc . dit to.
4 : rubbe r cast of e xte rnal mOLlld , left va lve, (KE 2753) , x 1.2, Lo c. ditto .
F ig. 5. Palliolum macrocheiricola I-l ABE (fo r comparison )5 : e xtern al vie w of ri g ht va lve, collected by iVIr. Ta ts uya MATSUMOTO, x 2, Loc. Tosa
bay of K ochi Prefecture.
Fi g s. 6-8. Thyasira (Thyasira) himedoensis, sp . no v .
6a: e xte rnal v iew of left v alve, ho lot ype (KE 2165) , x 1.2, Loc. north ern seashore of
KugLls hima is let, Ryugadake -machi , A mak usa-Ka mi shima, Ku mamoto Prefectur e .
6b: sa me specime n, x 2
7: ex te rna l v iew of conjoined val ves, s howin g the lunular are a, para type (KE 2774),
x 1. 2, Loc. ditto.
S: ex te rnal view of ri g ht v al ve , defo rm ed specime n, pa ratype (KE 2773), x 1. 2, Loc. ditto.
Fig.-9. Pycnodonte amalwsensis, sp. nov .
9 : inte rnal mould of left v alve , x 1.2, Loc. road side ex posure of north wes t beach of
Hinoshima island, A makusa-Ka mishima,: Kumamoto Prefectu re, .

TASHIRO:

Bivalves from the Himenoura Group

Plate 43TASHIRO:

Bivalves from the Himenoura Group

Plate 44

Ie

la

3b

4
ld

Ib

3a

8
2

7a
7b
5b

II

690.

On Some Interesting Bivalvesnian stage. KAUFFMAN (1967, 1969, 1976)
figured the morphological changes of these
species and subspecies through the Campanian. This species resembles Thyasira(s. str.) beauchampi s. str. which is oneof the earliest species from the Lower
Campanian of the Western Interior ofNorth America, in the features of surface
ornamentation, but differs from theAmerican species in having taller valves
and a weaker submarginal sulcus. It
resembles more closely Thyasira cretacea
WHITE AVES (ANDERSON, 1958) from theCretaceous of California (Lower Campanian by MATSUMOTO, 1959) than thespecies and subspecies of the WesternInterior, in the weak submarginal sulcus
and the nearly straight primary sulcus.
This is, however, more orbicular outline
than Thyasira creiacea.
Thyasira d.
towsendi WHITE (FRENEIX, 1960) from theSenonian of Noumea-Dumbea differs fromthis species in the more rounded andinflated valve.
Occurrence :-Black siltstone of the
middle member of the Lower Formationof the Lower Himenoura Subgroup at
northern seashore of Kugushima islet of
Ryugadake-machi, Amakusa-gun, Kumamoto Prefecture.
Middle Urakawan(Upper Santonian): Inoceramus japonicus
Zone.
REPOSITORY
The specimens (KE) described in thispaper are preserved in the Faculty of
Education, Kumamoto University (Kumamoto 860).
References
AI3I30T, P. T. (1955): American seashells. R.
Van Nostrand Co. Inc., New York. 5,11
pp., 40 pIs., 100 figs.
ANDERSON, F. M. (1958): Upper Cretaceousof the Pacific Coast. Ceol., Soc. America,
Mem, 71, 378 pp., 75 pIs.

327

COLLIGNON, M. (1951): Le Cretace superieurd'Antonibe, Couches de passage du Cretace au Tertiaire. Annales Ceologiques
du Service des Mines, Fascicule, no. 19,
186 pp., 7 pIs.
COSSMANN, M. (1922): Synopsis ilIustre desmollusques de I'Eocene et de I'Oligocene
en Aquitaine. Soc. Ceol. France, Mem,
Paliiont, vol. 24, fasc. 1-2, 113-220, 7 pIs.
Cox, L. R. (1964): Notes concerning the taxonomy and nomenclature of fossil Bivalvia(Mainly Mesozoic). Proc. Malac. Soc.
London, vol. 36, 39-48, pI. l.
- - and HERTLEIN, L. G. (1969): Family
Plicatulidae, Treatise on Invertebrate Paleontology, (N)Mollusca 6,(1 oj 3), p. N377N382.
FRENEIX, S. (1960): Etude complementairedes Lamellibranches du Cretace de Nouvelle-Caledonie. Sci. Terre, Tome 6(1958), nos. 1-2, p. 5-56, pIs. 1-3.
- - (1972): Les Mollusques bivalves Cre·
trees du Bassin cotier de Tarfaya (Maroc
meridional). Notes and M. Servo geol.
Maroc., no. 228, p. '19-255, 18 pIs.
HABE, T. (1951-1953): Genera of Japaneseshells. Pts. 1-4, 326 pp. (in Japanese)
HAYAMI, I (1975): A systematic survey ofthe Mesozoic bivalvia from Japan. Univ.
Museum. Univ. Tokyo, Bull., no. 10, 249
pp., 10 pIs.
HERTLEIN, L. G (1969): Family Pectinidae.
Treatise on Invertebrate Paleontology, (N)Mollusca 6, (1 of 3), p. N348-N373.
IcHIKAWA, K. and MAEDA, Y. (19;:;8): Late
Cretaceous pelecypods from the Izumi
Group, Part 2, Order Taxodontida, Priodontida, Dysodontida, Desmodontida andAdapedontida. Jour. Inst., Poly tech., Osaka City Univ., ser. G., vol. -1, p. 71-122,
pIs. 3-7.
KAliFn-IAN, E. G. (1967): Cretaceous Thyasira from the Western Interior of North
America. Smithsonian Misc. Coll., vol. 152,
no. 1, 159 pp., 5 pIs.
- - (1969): Form, Function and Evolution.
Treatise on Invertebrate Paleontology. (N)Mollusca 6 (1 of 3), p. N129-N204.
- - (1976): Dispersal and Biostratigraphic
potential of Cretaceous Benthonic Bivalvia

328

Masayuki TASHIRO

in the Western Interior. Ceol. Assoc.
Canada, Sp. Pap., no. 13, p. 163- 194.
MATSU:\\OTO, T. (1959): Upper Cretaceousammonites of California. Part 2, Mem.
Fac. Sci., Kyushu Univ., ser. D, geol., spec.
vol. 1, 172 pp., 41 pis.
STENZEL, H. B. (1959): Cretaceous oysters ofsouthwestern North America Congo Ceol.
Internac., XXa sesion, Ciudad de Mexico,1956, EI sistema Cretacico, vol. 1, 15-37,
19 figs.
- - (1971): Family Gryphaeidae. Treatiseon Invertebrate Paleontology, (N) Mollusca(3 of 3). p. NI097-N1126.
TASHIRO, :VI. (1976): Bivalve faunas of theCretaceous Himenoura Group in Kyushu.
Palaeont. Soc. Japan, Sp. Pap. no. 19, 102
pp. 12 pis.
WHITFIELD, R. P. (1885): Brachiopoda and
LameIIibranchiata of the Raritan Clay andGreen Sand Marls of New Jersey. U. S.
Ceol. Surv., Monogr., no. 9,338 pp., 35 pis.
WOODS, H. (1899-1903): A monograph of theCretaceous LameIIibranchiata of England.
Paleontographical Soc. London, vol. 1, 232pp., 42 pis.
ZITTEL, K. A. (1924): Palaeontologie, lnvetebrata. Verlag R. Oldenbourg, Milnchen
und Berlin, 733 pp.

Amakusa-Kamishima 7(1?=l:~,Bozujima :!1.i±'~,
Hinoshima t1!iz~,
Ryugadake t[i: ?-Hf,
Takagushi [\1Ii.$,
Wadanohana W8l.

Kugushima jf'~£'"

Explanation of Plate 44
Figs. 1-1. Atreta intulaevis, sp. nov.
la: internal mould of right valve, holotype (KE 2759), x 1,2, Loc. roadside exposure ofnorthwest beach of Hinoshima island, Amakusa-Kamishima, Kumamoto Prefecture
Ib: rubber cast of internal mould, the same specimen with la.
Ic: umbonal view of the same specimen, x 3
Id: umbonal view of rubber cast, same specimen.
2: sl1binternal mould of right valve, paratype (KE 2761), xI, Loc. ditto.
3a: internal mould of right valve, paratype (KE 2760), xI, Loc. ditto.
3b: the same specimen with 3a, showing radial striae and parallel threads of the internal surface, x 2
4: external mould of left valve, paratype (KE 2763), xI, Loc. ditto.
Figs. 5-11. Pycnodonte amakusensis, sp. nov.
5a: internal mould of left valve, holotype (KE 2765), x 1.2, Loc. roadside exposure ofnorthwest beach of Hiroshima island, Amakusa-Kamishima, Kumamoto Prefecture.
6: rubber cast of internal mould, left valve, paratype (KE 2766), x 1.2, Loc. ditto.
7a: internal mould of left valve, paratype (KE 2768), xI, Loc. ditto.
7b: umbonal view of same specimen with 7a, x 2
8: external view of left valve, rubber cast of paratype (KE 2770), xI, Loc. ditto.
9: external view of right valve, rubber cast (KE 2775), xI, Loc. ditto.
10: external view of right valve, rubber cast of paratype (KE 2771), xI, Loc. ditto.
11: external view of right valve, rubber cast (KE 2772), xl, Loc. ditto.

329

690. On Some Interesting Bivalves:1L m(J) ElilE**- illl ~ llf i£: (J)a; 7.> =tt J't: JTh:;$: ~!jr:R:ljtll1l 'Ii1 'T lir IIIJ (J) *-lIfj~ llf (J) r j'fflTII!
}<;!Jit1'rr.'Jb4S J: IJ i£:-r-7.> =tt.fl Atreta intuleavis, sp. nov., Pycnodonte amakusensis, sp.
nov., Thyasira (Thyasira) himedoensis, sp. nov., Chlamys (s.l.) tamurai immodesta,
subsp. nov. (J) 4 Jm 3 tfrfil! 1 tfrilli1ll!>a:'~c~ L t::.o .:t:(J)? i? Atreta, Pycnodonte, Thyasira lx,:;$:JiS*~W. -('Ix, t-;.:t: I? < :i&fJJ(J) ~c~-ea; 7.> (lEI. L, Pycnodonte? sp., HAY AMI 1975;
Thysira sp., TASHIRO 1976 >a:'~1i«). tJ::f; Atreta (J)fiJfN~lc0l'-Ctx, Plicatulidae
Dimyidae (J) ci? I? IClluk..l?n 7.> tJ,~rp'tJ:,~7'.6a; ') t::. tJ~, 4-@], 1ltr~lq1.-r- 7.> ;: c tJ;~Ij~ L t::.o
Pycnodonte ~ Thyasira tx, 77 Y ;/J, =" - p .y /~, ::It 7" Y ;/J -elt, ;/J :.//~.=. 7 :/tJIltf:IC.:t:(J)JGlttJ~~1if-c·a;7.>tJ;, :;$:i£:l1!!tx, -lj-:/ ~.=. 7 :/(J)rj'fflc ~n-Cl'7.>(J)-e, *-i!Il~llf&: (J)Pycnodonte, Thyasira tx, ill 'M~>a:'~-r- {, (J) L -C J;!,*~lit::., Chlamys (s.l.) tamurai, Chlamys (s.l.) tamurai immodesta tx, Camptonectes, Camptochlamys (J)*~f1;:ml(J) Pectinids c Eburneopecten, Palliolum (J)tfr~f1tml(J)Pectinids (J)"Zi(1Jlc.:t:n.:fn~D-r-7.>~OO • • >a:'~-r-7.>~, ~.~~, .~-C, R,*a;7.>{,(J)-ea;7.>oill f1t ~ ~

9l!'*

c

c

'0

330
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;~

fffitnljjW (;ftiZ!ij;::>fi'-'F) IC:j:;ft~Ii!i@~:j:;J:lf-tnc l3*cO)I*I:iY!IC".)t'-C····· ............ "j'fR fir
Coscinodiscus "yabei" 31' Iv - 7'0)*K!C5Hiilc ".)t,-C ............................. "j',* ~. 1:l-t1Hft,;ft¥laill:;R;ftJ:: $m~IE*£jlgmnt%?- 1 '/ ry ~m 1m ....•.......•.•.•.•....•....•...•...••... "j'M'fI!j*~J::$m~~*J£ Liquidambar O)7t~!,¥=Ef.J~iH····· .................................... ·:fffiM'f1Jjft*,~I\Yi~tJ:l?m;>:=pJ&@~£it1tl5lc".)t'-C····································· ·WdEllm5t· WiI$f*l/!;);;Jll!).PllW'lW'J: 1):f*J&UdHtl5IC".)t'-C ................................. 'ill~~*l/!j( ·IIIiJEIlm5t· ifOOEH$<rJ=PJ&K!C1!1i4&.J~lcJ£lli-t ~ "Jl1~" *1-I~lipc ".)t,-C ................................ , ........ ·t~Jii§3!!H:r1
Late Cretaceous Plants found from the Isla Quiriquina, Chile ...... KIMURA, T. & OHANA, T.
Late early Cretaceous plants from Fukui Prefecture, in the Inner Zone of japan··.·· ........ .
................................................................ KIMURA, T. & HORIUCHI, j.
Some coniferous and ginkgoalean remains from the Palaeogene Noda Group, Iwate Prefecture,japan (Part 4) ............................................... ·KIMURA, T. & HORIUCHI, j .
.I\l;J&!Ji!<!Ri3'*J£~~

7 f'/-{tl5IC ".)t ,-C .............................................. , ......... Jii§il$f0jft

On Phytosterol gained from Late Miocene fossil leaves····························· ·OZAKI, K.
~=PWJ,0..**mfJi1IO)~:JWBl!I!*c

7 p -7 ................................................... .;lllll:Jt~m~

Maklayia, from the Kuchibora Formation, Gujohachiman, Mino Massif, Central Japan· ·IGo, H.
:l'ii!!liW<gjHmO)l5lJl(~li!f!:E-J: 1)J£-t~*;Ij£il!£a1tl5 (-to) 1) -Jm!l!.fmJi:!:$O) Afghanella 1tl5f!"'" '~JirnJ'
Fusulinids from the Madre de Dios de ChilI and the Yaurichambi de Bolivia, South America··............................................ CHISAKA, T., CORVALAN, j. and URDININEA, R.
Revision of the Permian "stromatoporoids" reported from japan ............ ·.······· ·MORI, K.
15-lJ- /' ::r·O)1t~~ft!'¥= (Sclerochronology) IC ".)t '-C O)-~~ ..................................... .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 'H'§~= . *MIJJl JifE • 't-;~m:iI . 15'il1!.:9tr
Cladochonus, Amplexus, Lophophyllidium and their associated fauna of the L wer part of the
Ichinotani Formation, Hida Massif, Central Japan················· ·IGo, F. and ADACHI, S.
it-*~,!iI;Ji:!:$lc7)-;fp-t~J::$'i "-7*4'i1ll~~J£lliO)JIllJfliJl1tl50)1iIf9l;("}*) ......................... .

............................................ WI~Ujf;);;' 3±:Jt~~. ~~m~-· JiEH~r' fIlEllIDH
Some interesting fossils from the Late Paleozoic in Caraveli area, Southwest Peru············........................................................... ·YAMAGIWA, N. and RANGEL, C.
Bl!I!*1'iIIJmi1llRi1~.&lfJII J:JRi1iJ'I?J£-tM!9l. "Glauconia" IC".)t'-C ............... ':E-~~~' ~*11i*
7 'i7J£m1=.ft Amusium· ...... ·· .................................................... ·:J:!ljEll~-!\!~
fwil'ft;IiJJ;lI.*Ri1J£ Arcid-Potamid fauna IC".)\"-C ......................... "H1:)ffi~Im!\!~' !l!.fEH~i'f]::It¥la)Jtllt7J$IIITJ£ Vicarya ~~I;::".)t,-C ....................................... '~!I!.f~!\!~' :;R!I!.f;fU~
Macoma tokyoensis MAKIYAMA C Macoma totomiensis MAKIYAMA IC".)t,-C ................... .

..... .. .. .. .. .. .. .. .... .... .. .. .. .. .... .. .. .. .... .. .......... . TI!I!.f~!\!~ • :J:!ljEH'M±JifE • :;R!Ilf;fU~

m=fk**-" '/ * ry A -Jl1 ~W~~O)~;Dh··· .. ······ .. ·· .... ·········•···· .. '~EIl~±ft!! (JECOLN)

331
Notes on Lewesiceras and Nowakites (Pachydiscid Ammonites) from the Cretaceous of lIokkaido.•.•••••...••••••••••••••••••••• ·c· .~••••• ' ............: •• : . . . . . . . . . . . . . . . . . . . . MATSUMOTO, T.
13*ii€""vA*c':::~!RIC0l'-C(WJjq'jl.11b~" '8~1J;l,3M[!lmm~f'l)11)....................... ·'HR.. 1f

I3*O):fii.J{*c':::~~!R)!g*······················································· ·'N*J!.I- "1JUBIlif;±

JiIHYj7:;Y.:::l'l:" ::fiW{*[l,~'lIt!RifJ'V*····· ...................................... ···'N*j[- "*EBIlif;±g§j('F-~T~~bO)::fiER*C.:::'lIt!RO)J:~tc·······'.......... : ................... ', ....... "N*j[- " ~EBIlif;::I:

Ontogenies of four Upper Cambrian trilobites from the Bonneterre Dolomite, Missouri· . :·· '.' .
.......................................................... , ................. lIu, C.-H. (t\;ltJj;)/~:f- 7-31 :/, "/ 'v r 1/:/:; 7Jc.lf"h '/ ~ - 'l.-:li!!.Jr£O) r I} 7 7.iFClltrJUJ ::l / r":/ Ht.::fi· .... , : ......... f'lEBT1f:1C
Permian conodont zones in· Japan ...................................................... ·lGo, H.
On some Tertiary ophiomorphids .................................................. :. ·NODA, lI.
"" c:!lli El IC YOl<:ozuchidae Yokozuchis tokuyamai ~~O)j1eIIU ........................... ·li7rjN;R:zJJ;l]332

PALAEONTOLOGICAL SOCIETY OF JAPAN, SPECIAL PAPERS, NUMBER 23 'k' 1979 :¥Ilh::.
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Transactions and Proceedings of the PalaeontologicalSociety of Japan

New Series No. 110

June 30, 1978

CONTENTS
TRANSACTIONS
688. OKUDA Hisashi, and YAMAGIWA, Nobuo: Triassic Corals from Mt. Daifugen,
Nara Prefecture, Southwest Japan .................................... 297
689. MATSUMOTO, Tatsuro and HARAGUCHI, Yoshimitsu: A New Texanitine
Ammonite from Hokkaido (Studies of Cretaceous Ammonites from
Hokkaido and Saghalien-XXXIV) ...................................... 306
690. TASHIRO, Masayuki: On Some Interesting Bivalves from the Cretaceous319
Himenoura Group in Kyushu
PROCEEDINGS ................................................................ 330