九州大学学術情報リポジトリ Kyushu University Institutional Repository

A Monograph of the Collignoniceratidae from Hokkaido Part Ⅲ : Studies of the Cretaceous Ammonites from Hokkaido and Saghalien-XX

Matsumoto, Tatsuro Faculty of Science, Kyushu University

https://doi.org/10.5109/1543680

出版情報：九州大學理學部紀要 : Series D, Geology. 19 (3), pp.297-330, 1969-11-10. 九州大学理学 部 バージョン： 権利関係： Mem． Fac． Sci．， Kyushu Univ．， Ser． D， Geology， VoL XIX． No．3， pp．297－330， text－figs．1－14， pls．39－45， Nov．10，1969

AMonograph of the Co1Hgnoniceratidae ffom Hokkaido Part III

（Studies of the Cretaceous Ammonites from Hokkaido and Saghalien－XX）

By Tatsuro MATsuMOTO

Abstract

Part III contains the systematic descriptions of the subfamily Barroisi－ ceratinae． The hitherto used framework of classification of the Barroisicerat－ inae is to some extent modi6ed． Bα88θocθγα8 C旺LIGNoN，1965， is regarded as asubgenus of Bαγγoτ8i6θゲα8， whereas Tθ出α8ぜαis separated as a distinct genus． Anew subgenus of Foγγθ8εθ万αis established which is characterized l）y a smoothed outer whorl． This is morphologically transitional to more evolute yα6θi6θγα8， which is settled as a specialized offshoot in the Barroisiceratillae． The described species from Hokkaido are altogether seven：－a new species of Bαγγo衙6θγα8 （Bα88θ06θγα8）， two species of Foγγθs亡θ冗α （Foηθ8£eγ‘α）， including world－wide 17．（F．）α伽α履Z in a revised sense and a new one， two new species of a new subgenus of Foγγθ8¢θ励α， a species ofγαbθづ6θγα8 and a species of 17αγZθ社θ8． In connection with the descriptions of the barroisicera七ine ammonites from Hokkaido， comments are generally given on many genera and subgenera， and also on some species occurring outside Hokkaido．

Contents

P2233333333333333a e Systematic De．scriptions（continue．d）．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．，．．．．．．． 990000001112222298801367835702478 Subfamily Barroisiceratinae．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．

Ge．nus Bα”oi8τoθγα8 DE GRossouvRE，1894．．．．．．．．．．．．．．．．．．．．．．．．，．．．．．

Subgenus Bαs8θooθγα8 CoLLIGNoN，1965．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．

B．（Bαs8θ06θγα8）τγ10竹ταZμγηsp． nov．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．

Genus Fo”θ8舌θ碗αREEsIDE，1932．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．◆．

Subge．nus Fo性θ8τθ万αREEsIDE，1932．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．． F．（F．）α1伽α批況（BouLE， LEMoINE and THEvENIN）．．．．．．．．．．．．．．．．．

F．（F．）αwηαfαsp． nov．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．

Subgenus 1∬2ぴαγηo施αnov．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．． F．（1∬．）〃θzoθ旭8 sp． nov．＿＿＿＿＿＿．＿＿＿＿．．＿＿．．． F．（刀4．）？η祝7・α？ηo亡o元sp． nov．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．

Genus Yαbθτoθγαs ToKuNAGA and SHIMIzu，1926．．．．．．．．．．．．．．．．．．．．．．． γ．o〆α励α1θToKuNAGA and SHIMIzu．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．

Genus 1了αゲ1θπθ8 REEsIDE，1932．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．

H．sp． cf． H．んαγ1θτ（DE GRossouvRE）．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．

Manuscript received July 5，1969． 298 T．MATSUMOTO

Systematic Descriptions （Continued）

Subfamily Barroisiceratinae

The subfamily Barroisiceratinae BAssE，1947， were comprehensively studied by REEsIDE（1932）and BAssE（1947）． The framework of the classi6cation used in the Tγθ硫8θby WRIGHT（1957）is in principle acceptable， as was previously supPorted by REYMENT（1955）． There are subsequent works which should be taken into consideration， such as those of YouNG （1963）， PARNEs （1964）， ］M［ATsuMoTo et al．（1964）， CoLLIGNoN （1965） and the late Dr． vAN HoEPEN （1968）． Although the Cretaceous deposits of Hokkaido are not so prolific in the Barroisiceratinae as those of Madagascar， our recent collections， aided much by Mr． T． MuRAMoTo， contain some interesting examples． As a result of the study of them and also the survey of previous works， I modify to some extent WRIGHT’s scheme of classi丘cation． In view of the high variabiIity of the barroisiceratine ammonites， as demonstrated by BAssE’s（1947）6ne work， too much splitting in classification should be avoided． Several superficially distinctive groups of species are treated as subgenera， whereas a few apparently resembling ones are separated as distinct genera， inasmuch as there are suf6cient reasons． The Barroisiceratinae are typically represented by Bαγγo乞8Zcθγα8 and range in shell characters from comparatively more compressed， feebly ornate or smooth－ ish genera， such as Solgθγ伽8 and丑αγZθ屹8， to more in且ated， strongly ornate ones， such as Fo”θ8亡θγ‘α（s．s．）alld S励bαγγoZ8icθγαs． Two major stocks， one without and the other with mediolateral tubercles， can be distinguished in the subfamily， but the mediolateral tubercles themselves may become apparently variable in the case when the smoothing of flanks takes place（as in Solgθγ屹8 and丑α冗θZτθ8）． In other words， the af丘nity of Bαγγo乞8Z6θγα8 with a smoothed outer whorl（e．g． Bα88θooθγα8）and that of Fo宵θsτθγZαwith smoothed flanks （e．9．Solgθγπθ8） may be confused unless the ontogenetic change of characters in the inner whorls is carefully inspected． Many species of the Barroisiceratinae have fairly or very involute shells， but Foγγθ8君θγZαincludes less involute species． yαbθZ¢θγα8is regarded as a specialized offshoot of the Foγγθ8¢θがαstock charac－ terized by evolute shells， more or less depressed and strongly七uberculate septate whorls and a smooth body－whorl． A new subgenus（2∪「τLγα7η0¢0α）of 170γγθ8τ碗α to be established below seems to represent an intermediate form between 170γ一 γθ8εθγZα （s．s．） and yαbθZ6θγα8． Sutures are also considerably variable in the Barroisiceratinae． Those of BαγγoZ8Z6θγαs may show the average pattern， al－ though they vary to some extent in themselves． Comparatively reduced patterns are seen i11∬αγ1θ舵8， whereas more deeply indented ones characterize 8励bαγ一

γoZ8τ6θγα8 and yα6θτ¢θγα8．

The origin of Bαγゲoτ8Zcθγα8 isl certainly in S励p万oη06y¢伽80f the Upper Turonian， as has already been mentioned by WRIGHT（1957， p． U32）．1～θθ8鰯¢θ8 AMonograph of the Collignoniceratidae from Hokkaido． Part III 299

WRIGHT and MATsuMoTo，1954， another derivative of Sμ吻乞oη06〃鋤80ccurring near the Turonian－Coniacian boundary， indeed resembles Bα宵oZ8i¢θグα8 in some respects but is more closely related to劫bpγZoηoc〆μ8， as has been described in detail in Pαγ¢10f this monograph（MATsuMoTo，1965， P．62）． It could be possibly a passage form between S？L吻γ‘oηoc〃61μ8 and Bα㌍γoi8乞6θγα8， but I am rather inclined to regard it as a dead end offshoot of S％bP弼oη062／61μ8， because its much compressed shell－form， Hexuous ribs， bullate umbilical七ubercles， and modi6ed pattern of sutures imply deviation from the normal characters which connect Bαγγoτ8乞cθγα8 with S秘伽弼oηρo〃clμs． A］most all the genera and subgenera of the Barroisiceratinae are strati－ graphically confined to七he Coniacian， except that Tθ鋤8iαis informed by YouNG （1963）to range up to the Lower Campanian． The zonal succession of various species of the subfamily in七he Coniacian has not yet been well estal〕lished， inspite of their frequent occurrence in certain areas． According to Co肌IGNoN’s （1965）atlas of characteristic fossils in Madagascar many of the illustrated species belonging to BαγoZ8τcθγα8（s．s．）， S励bαγ㌍o乞s乞cθγα8，Hα弼θπθ8， Foγγθs¢θ？・iα （s．s．）， YαbθZoθγαs and SoIgθγττθ8（two species）occur in the Middle Coniacian zone of瓦088仇α臨θγα8毒んθobα臨αημ伽一 Bαγγo‘8Z¢θγα8 0γz江αん2ノ¢η8θ， several of Solgθγπθ8 ［＝Pをりθfθαμ0¢¢γα8］ and Bα88θo－

6θゲα8in the UpPer Coniacian zone of Pγ乞oηo¢yclo6θγαs gμ〃αbαημ仇一Gα励ん乞θガ6θγα8 仇αγgαθ，whereas three species of Yαbθi6θγα80ccur already in the Lower Conia－ cian zone of P¢γo傭θγα8由励輪襯． Whether this succession is everywhere main七ained in Madagascar and other regions or otherwise should be examined by further study． The available evidence in Hokkaido is not su伍cient on this acco皿t． All the species from Japan occur in the zone of 1％06θγα働秘8％ωα∫‘一 仇θη8i8． In our present knowledge it may be broadly stated that most of the barroisiceratine genera and subgenera seem to have been rather suddenly dif－ ferentiated directly or indirectly from the common ancestor，品bpγ40ηoo〃61μ8・ The geographical distribution of the Barroisiceratinae was summarized by BAssE（1947， p．161－170， especially text－figs．6－7）， who concluded that they are distribu七ed in a considerably wide belt on both sides． of the postumed Late Cretaceous equator． Japan was not included in her distribution map． The occurrence of various species belonging to various genera and subgenera of the subfamily has become distinct in the present study． Hokkaido as well as the Pacific side of Northeast Japan must have been under the influence of七he ocean curren七from the south in addition to七hat from the north or northeast． The reason why the Barroisiceratinae have hitherto been overlooked from the study of the proli且c Upper Cretaceous of Hokkaido is， in my view， in facies problem． In Hokkaido as well as in Northeas七Japan，七he barroisiceratine ammonites occur almos七exclusively in comparatively shallower， more or Iess sandy（and glauconitic）open－sea sediments but are extremely rare in probably off－shore muddy sediments． While the strata of the Iatter facies are widely distributed in Hokkaido， those of the former facies are limited there． 300 T．MATSUMOTO

Genus BαγγoZ8τcθγα8 DE GRossouvRE，1894

欠〃Pθ一8Pθo‘θ8・一∠4γηηzoγτ党θ8 んαbθ7プθZZ？zθγZ］旺AuER，1866 （subsequent designa－ tion by SoLGER，1904）． Gθηθγ乞6伽gη08ぜ8．－Whorls are moderately involute， more or Iess higher than broad， and usually broadest in the lower part（i．e． near the umbilicus）， having compressed to considerably inHa七ed flanks and a rather low， roof－shaped venter． The ventral keel is typically strong and七he clavate ventral tul〕ercles give rise to distinct serration on the keel． From rather sparse umbilical tubercles arise radial ribs which are alternated with one or two shorter ones． All the ribs form clavate tubercles at the ventro－ lateral shoulder and then projected to the ventral clavi． The umbilical tubercles are typically ro皿ded at least on the inner whorls but may sometimes be bullate． Normally the radial ribs are rather flat． AI七hough the suture is considerably variable， the first lateral lobe（L）is moderately deep and asymmetrically bipartite and the Iateral saddles on both sides of L are massive to subrectangular in rough outline． The number of auxiliary elements is apparently variable． The saddles and lobes are moderately indented． The main lobules in the two lateral saddles and七he folioles in the lower part of L may be considerably long and narrow． Other minor incisions are generally small， showing a rather reduced aspect of the suture． The size of the shell is small to moderate． Rθ仇α触．－In the欠γθα万8θ（WRIGHT，1957， p． L432）two subgenera， Bαγ一 γoZsぜoθγα8（s．s．）and Tθぽαs乞αREEsIDE，1932， are included in七he genus Bαγγo乞8ε一 〇θγα8． Flor the reasons described below I think i七be七ter to separate T斑α8iα as a distinct genus and treat Bα88θ06θ㌍α8 CoLI、IGNoN，1965， as a subgenus of Bαγo‘8ゼ¢θγα8． The above described generic diagnosis is七ypically applied to the Subgenus BαγγoZ8‘¢θγαS （S．S．）．

Ihad an opportunity to examine two syntypes of∠4働仇o励εθ8∂θ励ατ06αγ励α一 施8R6MER（1852）， the type－species ofτθωα8‘αREEsIDE，1932， in七he University of Bonn（G．1．B． No．48a and 48b）（Text－figs．1－2）． The larger and illustrated one （R6MER，1852， pl．1， fig．2a－c） is designated here as the lectotype． The smaller one is of identical species． In these specimens the major ribs which arise from the umbilical tubercles are somewhat elevated at七he middle of七he Hank， if not forming distinct tubercles． The ribs are somewhat weakened be－ tween this row of elevations and that of ventrolateral七ubercles． Some of the ribs show a slight bending at the elevating point． These characters， though indistinct and overlooked by subsequent authors（e．g． LAsswlTz，1904；REEsIDE， 1932；YouNG，1963）， and the compressed whorls with Hattened flanks and also very deeply incised sutures with an apparently trifid first Iateral Iobe， may indicate a possible afnnity of Tθzα8Zα（1θ励ατo¢αγ仇α診αwith such species as P8θπ∂08c〃lo梛bα6Mα仇θ励oαηα （RENz，1936）（see YouNG，1963）， although七he ventral keel is more distinctly serrate in欠θ鋤8づα． 欠．∂θ励ατocαγ碗α£αoccurs， according to YouNG（1963， P．120）， in the upPer－ most Santonian and the Iowest Campanian． Tθ影α8Zα鋤γ亡o励（REEsIDE）（1932， AMonograph of the Collignoniceratidae from Hokkaido． Part III 301

、 〜ー ／，， ・

、

1b 2b

20

20mm － Figs．1－2． Tα履α8iαdθ励α¢06α㌍仇α£α（R6MER）

Two syntypes， No．48a（Fig．1）and No．48b（Fig．2）， in the Palaeontological Museum， University of Bonn． Lateral view（a）and whor1－section（b）in diagram－ matic sketch． （T．］M．（1θliγτ．） p．16，p1．6， figs．7－9；pl．7，6gs．8，9），which is reported as older than T．〔Zθ励α£o－ ¢αγ仇ατα，seems to show slight thickening of the ribs at the mid－flank and weakening above that point． These species are more evolute than typical species ofBαγγo乞8τcθγ。α8．

REEsIDE （1932， pl．3， figs．9－10；pl．4， fig．3） described under T．（1θ励ατo－ 6αr飢α施alarge shell which has prominent and distant ven七rolateral nodes on otherwise smoothish body－whorl． This is a remarkable feature which is not seen in Bαγγ0ゼ8i6θγα8 （S．S．）． To sum up欠θωα8Zαconsiderably deviates from Bαγγo‘8Zcθγα8．

In the Cretaceous of Hokkaido no examples of BαγγoZ8icθγα8（Bαγγo‘8τcθγαs） have been found， but there is a species which is referable to B．（Bα8sθooθγα8）．

Subgenus Bα88θ06θγα8 CoL・LIGNoN，1965

欠鯛）θ一81）θ6乞θ8．－Bα88θ10cθγα8 col6αηαpZ CoLI・IGNoN， 1965 （original designa－ tion）． 8励gθηθ酩砺α9η08乞8．－This subgenus resembles Bαγγoi8Zcθγα8（BαγγoZsτ一 6θγα8）in the earlier growth－stages， but is distinguished by the disappearance of the ribs and tubercles in more or less late growth－stages． The ventral keel is also weakened and may disappear in the nnal stage． In other words七he ou七er whorl is smoo七hish． Even on the inner whorls the ribs are weakened on the Hank． Co仇PαγZ80ηα励ゲθ伽αγ”s’－Bα88θocθγα8 was set uP by CoLロGNoN （1965， p．73）as a new genus of the Barroisiceratinae． Itrea七it as a subgenus of BαγγoZ8乞cθγα8， because it is closely related to Bαγγoゼ8Zoθγα8 （s．s．） and because BαγγoZ8ぜcθγα8（s．s．）is greatly variable and some examples show transitional 302 T．MATSUMOTO features to Bα88θo¢θγα8． In fact， if the imma七ure specimens alone are handled， it may be sometimes dif丘cult to tell whether they are referred to B．（Bαγγo乞8i－

6θク’α8） or to B． （Bα88θOCθγα8）． In addition to the type－species I should include ln Bα8sθ06θγα8 more specles ウ which have essentially the same charac七ers as Bαγγo乞8Z6θγα8（s．s．）in earlier growth－stages and lose the ornament in later grow七h－stages． In B． ooloα物αp‘ all kinds of ornament disappear rather suddenly in the adult stage， as is clearly described I）y CoLI．IGNoN（1965， P．74， pl．447， fig・1826）・壬 But in certain other species， e．g． a new species described below， the ornament is weakened in an earlier grow七h－stage and it disappears rather gradually． CoLuGNoN reckoned七he upward shif七〇f the umbilical tubercles with growth as asubgeneric character． This is， in my opinion， not so significant， since a similar feature is discernible in some examples of Bαγγo緬6θγα8（s．s．）． Other species which I am going to refer to．Bα88θ06θγα8 do not necessarily show this character． In the reduced ornamentation Bα88θoeθγαs is similar七〇SoIgθγifθs REEslDE， 1932．In this connexion some remarks should be given on the latter genus． 801gθγπθ8 was established by REEsIDE（1932， p．14）as a subgenus of Bαγ一 γ068Z6θγα8 for the group of B．扮αη¢oゼSoLGER，1904． As the specimens of B．bγα竹coZ are no七accessible to me， I have to depend on REYMENT，s revision （1958，p．65）a8 well as SoLGER’s original description（1904， p．174， p1．5， figs．4， 5）to understand what B． bγαη¢oゼreally is． Unfortunately the best preserved syntype（No． I specimen of SoLGER，1904， pl．5，丘g．4；reproduced in the野θατゼ8θ， fig．551－1）is missing． According to REYMENT， as well as SoLGER， No． III speci－ men is identical with No． I and No． II． Then i七follows that B．6γαη60τevidently has weak mediolateral tubercles on the immature whorls． Until I could look at SoLGER’s specimens and／or a good collection of a population from the七ype－ locality， I should follow REYMENT’s observa七ion． 80Zgθγ批8 in this sense is probably a derivative of a compressed subgroup of．Fo”θ8曳がα， with attenua七ion of the orllament．801gθが¢θ8 should， thus， be separated from Bαγγoτ8‘¢θγα8 as a distinct genus． In other words， Bα88θ06θγα8 and 801gθγ‘τθ8 are probably superficially resembling， parallel developments in the Barroisiceratinae． As WRIGHT（1957， p． L432）has pointed out， P初θτθαμooθγα8 BAssE，1947， falls in the synonym of 80Zgθ励θ80f the above interpretation， because its type－ species， P初θ¢θαμ06θγα8θboγoθη8θBAssE， likewise has small mediolateral tuber－ cles on the inner whorls， as BAssE（1947， p．143）herself clearly described and as REYMENT（1954， p．265）discussed． Minor differences in the shell－form， um－ bilical margin， pattern of sutures， etc． would not deserve good criteria to distinguish the two nominal genera． In 801gθγ屹8 bγαη¢oづthe umbilical tubercles are weak even in the immature stage and almo8t absent in the main stages， whereas the outer half of the ribs and also the ventrolateral tubercles persist to a later stage． In Bαγγoτ8τ6θγα8 （Bα88θo¢θγα8）60Z¢耽αpゼ， on the contrary， the umbilical tubercles are fairly

＊The plaster cast of the llolotype of B．60Z6αηα餌was kindly sent to me through Dr． J．SORNAY． AMonograph of the Collignoniceratidae from Hokkaido． Part III 303 strong in the immature stages and evidently persist to a Iater stage than in 8．bγαηco乞． This can be taken as one of the generic criteria． In this respect， Bαγγo‘8i6θγα8γowτiθ秘出Z PERVINQuERE（1907， P．383， pl．12， fig．12；text－fig．104）， from Tunisia， is prol）ably referable七〇Solgθγ乞£θ8， although its inner whorls have not been satisfactorily examined． When the above interpretation of 80膓gθ碗θ8 is accepted， some of七he species which were previously referred to 801gγ党θ8 should be七ter be replaced to Bαγγoτs乞一 ¢θγα8 （Bα88θ06θγα8）． For instance， Solgθγ乞τθ8607zgoθ？zsi8 BAssE （1947， p．125） ［＝Bαγγoゼ8icθγα8んα6θγ∫θ励θγτ， LoMBARD，1931， P．298， pl．31］， from the Coniacian of Congo， is either an example of Bα88θocθγαs or a七1east an intermediate form from Bαγγoi8Z6θγα8（Bα”oゼ8Z6¢γα8）七〇B．（Bα88θooθγα8）． The species from the Celendin Formation（Bμ¢厄cθγα8 bZZobαfμ蹴zone）of Peru， described under Bαγoi8乞cθγαs（Solgθγ飽8）bγαηco乞by BENAvlDEs－CAcEREs （ユ956，p．477， pl．58， figs．1－4）is another example of Bα88θ06eγαs． A new specific name， Bαrrojsjcθrαs（Bα88θocerαs）pθrωujαημ7ηsp． nov．， is proposed here for it． The species is established on two specimens， A． M． N． H． No．27887／1（holtoype） and 2（paratype）． It is distinguished from 80Zgθγπθ8 bγαη¢oZ by the coarser and stronger ribs， more dis七inct umbilical tubercles and the absence of medio－ lateral七ubercles on its inner whorls． It has a more compressed and more involute shell， with a higher roof－shaped venter， and more numerous and more slender umbilical tubercles than BαγγoZ8乞6θ？・α8 （Bα88θocθγα8）¢ol¢αηαpZ（CoI．LIGNoN）． Even in the smoothish outer whorl B．（Bα88eo6θγα8）pθγ伽Zαημ仇is distinct in its very high and compressed section and persistency of七he fastigate venter． Therefore， it is somewhat similar七〇Hαγ1碗Zθ8 in shell－form， but i七has no mediolateral tubercles and i七s ventrolateral clavi are no七so persistent and its suture is not so reduced as in正1αγ1θ“e8． Incidentally the illustra七ed specimen of U〕THY （1918， p．48， p1．4，且g．1） under 86んloθηbα6〃乞α（Bαγγo乞8乞cθγα8）恒αη606 var．勿砺8 SoLGER， which has weak mediolateral tubercles on the 6ne ribs， cannot be identified with B．（Bα88θ06θγα8） pθγ耽乞α拠批here de6ned， but is probably an example of true Solgθ働θ8 from Peru． 801gθγπθ8¢z功θγ仇Zα¢秘8 REYMENT（1954， p．267， pl．2；text－fig．11；1955， p1．17， 6g．5）， from the Coniacian of Nigeria， is again another example of B．（Bα88θo－ cθγα8），because it has no mediolateral tubercles and is very similar to species of Bαγγoゼ8乞6θγα8 in the stages preceding to the smooth last s七age．

Bαγγoτsぜ¢θγα8（Bα88θooθγα8）仇oγηα九勿sp． nov．

P1．39 ［27］，Fig．1；Text－figs．3－4

丑oloε卯θ．－GK． H5460， from the zone of 1πocθγαmμ8μτoαグ拠θη8乞8， Pombets Gono－sawa（Coll． T． MuRA］MoTo， P5－6234）．

1レfθαsτLγθγη杉γz亡s．一

Diameter UmbiliCUS Height Breadth B．／H． GK． H5460 80．0（1） 12．8（．16） 40．5（．51） 24．6（．31） ．60 〃 （－160°） 54．5（1） 8．5（．15） 31．5（．58） 21．4（．39） ．68 304 T．MATSUMOTO

．ψ

弘，，

v．グ

∂

〃 b q 20mm － Fig．3． Bαrγo元sτ6θγ1α8（Bα88θooθγ唱α8）カτoγγλα¢祝？ηsp． nov．

GK． H5460， holotype． Diagrammatic sketches of lateral（a）and frontal （b）views． （T． M．∂θ励．）

L ε

∪3（rS））

5rnm

Fig．4． Bα㌍㌍oτsτ¢θγα8（Bα8sθooθγα8）力己oγワzαれ¢γ7z sp． nov．

GK． H5460， holotype． External sutures at whorl－height＝25 mm． （T．M． dθ1τγτ．）

1）‘αgη08ぜ8．－The shell is rather small， Iess than 100 mm． in the diameter of the adult stage， involute and narrowly umbilicate． The whorl is considerably higher than broad， showing about 10：6＿7 in the proportion of height to breadth， and broadest in the lower part（i．e． near the umbilical shoulder）． The umbilical wall is overhanging and the umbilical shoulder is subangular． The flanks are slightly convex and convergent． There are obtusely subangular ventrolateral shoulders；七he ven七er is narrow and roof－shaped with a Iow median keel． The keel and the ventrolateral shoulders are weekened but remain in the main part of the body－whorl． In the final part of the body．’whorl the keel is almost lost and the venter is gently arched． AMonograph of the Collignoniceratidae from Hokkaido． Part III 305

The surface of the body－whorl is nearly smooth， except for the prorsiradiate lirae on the flank， faint serration on the week keel on its posterior half and a few， occasional， blunt， remnants of ribs and umbilical bullae． In the preceding stage， i．e． on the main part of the septate whorls there are sparse umbilical bullae， faint ventrolateral clavi and fairly distinct medioventral clavi which correspond in number to the ventrolateral ones． No mediolateral tubercles are discernible． The orllaments of earlier whorls are concealed in the holotype． The suture in the adult stage is deeply and fairly finely incised． Especially the 6rst lateral lobe （L） is so deep that it is overlapPed by a part of the saddle of the immediately preceding suture（see Fig．4）． The sutural pattern is some－ what peculiar． The丘rst lateral saddle（between E and L）is subrectangular in rough outline， apParently tripartite， having a very deep， vertical lobule on七he inner side （i．e． closer to L）． The first lateral Iobe （L）is the deepest， sul）－ rec七angular in rough outline， divided into several deep branches in the lower part by narrow， upright， folioles of dissimilar heights． The second la七eral saddle （between L alld U2）is again irregularly tripartite， having a deeper lobule on the outer side（i．e． closer to L）． The auxiliaries are gellerally descending， but the lobule at the umbilical shoulder is unusually small． Finely subdivided folioles show somewhat phylloid terminals in some parts． Rθ仇α励8．－Only a single specimen is available at present， but its observed characters are so diagnostic that it is regarded as representing a new species． Co糀忽αγτ80η．－The present species is distinguished from Bαγγo乞8乞6θγα8 （Bα88θo¢θγα8）¢oZcαηαpづCo肌IGNoN（1965， p．74， pl．447，血g．1826）， from the Coniacian（zone of Pがoηo¢〃cZo6θγα8 gWαbα％μ働）of Madagascar in its more compressed whorls（b／h＝0．6＿0．7 as compared with O．8（十）of．8． oolcαηα餌）， smaller umbilicus（u／d＝0．16 as compared with O．260f B． col6耽αp乞）， finer ventrolateral clavi and weaker and bullate umbilical tubercles which do not shift upward on the outer whorl． BAssE （1947）6nely demonstrated the great variability of BαγγoτsZcθγαs o捌α吻θη8θBAssE， in which ornaments sometimes tend to become weak and delicate． It is noted that the described specimen from Hokkaido somewhat resembles one of the illustrated specimens of B． oηZIα吻θη8θBAssE（1947， pl．4， 6g．2），although the former has more compressed whorls and still more weakened or nearly obsolete ornaments． The resemblance suggests that the present species could be derived from a certain species of BαγγoZsZcθγα8（BαγγoZ8Z6θゲα8）by weakening of ornaments and by compression of whorls． The difference in the pattern of sutures between the two species is considerable， but the great varia－ bility in sutures of Bαγγo乞8Z6θγ・α8 as illustrated by BAssE seems七〇imply that such a particular pattern of 8uture as the present species could be led from a Hexible suture of Bαゲγoi8乞6θγα8 （s．s．）．

The present species is super丘cially similar to．P初θ¢θαμocθγα8θboγoθη8θ BAssE（1947， p．142， pl．33［9］，丘gs．4，5），from the Coniacian（‘‘Eboro bed”）of Madagascar， in the shell－form， generally smoothish surface， and mode of the ventral ornament8． The Eboro species， which should be referred to Solgθ励θ8 as discussed above， is provided with small mediolateral tubercles in a certain 306 T．MATSUMOTO

growth－stages． B．（Bα88θ06θγα8）仇o推α£μ伽has no mediolateral tubercles and more compressed whorls． Its suture is distinct from 80Zgθγ伽8θboγoθη8乞8 in the Iong， narrow and upright folioles and lobules of L and adjacen七saddles． B．（Bα88θo¢θγα8）仇oγηα枷物resembles Solgθ働θ8（？）1αθ励8 BAssE（1947， p．125，pl．15［9］，6g．1；text－fig．4）， from the Coniacian （‘‘Eboro bed，，）of Madagascar， in the smoothish and compressed shell． The two species are similar in the general pattern of suture， but differ in details as can be understood by comparing the text一負gures． The umbilical margin is subangular and overhanging in the Hokkaido species， but it is rounded in the Madagascar species． The ventral keel and the ventrolateral angulations are weakened but persist to the posterior part of the body－whorl in the former， whereas they disappear earlier and the venter is more rounded in the latter． Incidentally，80ZgθγZεθ8（？）1αθ励8 BAssE may be referable to Bα88θocθγα8． The descril）ed holotype of Bαγγo‘8Z6θγα8（Bα88θ06θγα8）仇o推αZz棚shows an interesting feature that the body－whorl七ends to become less involute， with widened umbilicus， and to be slightly decreased in height at七he Iast stage． This scaphitoid character cannot be overlooked as accidental， since a similar feature is observable in some species of 8εol㌘んα‘α（see SpATH，1931， p．328）， 刀Zα励θIIZ6θγα8（see MATsuMoTo et al．，1969， P．253 and p．258）， and Afθ加‘cooθγα8 （see HYATT，1903， pl．13， fig．4；pl．14， fig．7；CoBBAN，1953， pl．9）， as well as inτθκα8Zα（see WRIGHT，1957， p． L432）． 06¢視γγθη6θ．－Gono－sawa（i．e． the 6fth tributary）of the Pombets， a branch of the Ikushumbets， central Hokkaido． The described specimen was found by T．MuRAMoTo in a calcareous nodule of greenish dark grey， sandy siltstone， along with numerous specimens of 1πocθγα仇μ8秘ωαグ碗θη8Z8． The age is， accord－ ingly， Lower Urakawan， apProximately Coniacian．

Genus Foηθ8彦．θ冗αREEsIDE，1932

8鋼o吻物〃．－CoZZZgητoη乞6θγα8 vAN HoEPEN， 1955 ⑰oη ColZ乞9ηo励cθγα8 BREIsTROFFER，1947）；CoZI乞9ηoηθZIαVAN HOEPEN，1957． τ〃pθ一8pθoZθ8．－BαγγoZoZ8θゲα8（Fo”θ8舌θγZα）∫oγγθ8τθがREEslDE，1932（original designation）［＝170γγθ8τθηααIZμαzL（Zτ（BouLE， LEMoINE and THEvENIN，1907），as described below］． GθηθγZ6砺αg％08‘8．－The shell is typically moderate in size， about 80 to 100mm． in diameter at the adult stage， but larger in some species and smaller in others． The involution is moderate；the umbilicus is typically 25±5 percent of the shell diameter， but may be of variable width． The whorl is nearly as high as broad， or more or Iess broader than high， or勿乞6θ勿θγ8α， being fairly variable in section． The ventral keel is dis七inct． The omament is typically strong． It consists fundamental of rectiradiate ribs， with intercalation or bifurcation of the shorter ones at about the middle of the flank， umbilical， mediolateral， ventrolateral and medioventral tubercles． The tubercles are generally strong． Especially the mediolateral ones are AMonograph of the Collignoniceratidae from Hokkaido． Part III 307 prominent in the middle growth－stages． The umbilical tubercles may be some－ times weaker or indistinct． The ornamellt may be modi6ed in various ways， giving distinction between subgenera or species groups． The suture has rather massive lateral saddles on both sides of rather narrow L and is moderately indented， but may be variable in minor details． Rθ伽α袖s．一、Poγγθ8亡θがαwas established by REEsIDE as a subgenus of Bαγ一 夕o乞8ぜ6θγα8，together with subgenera Tθ鋤8τα， AZ8εαdθ励古θ8 and五rαγZθπθ8． I agree with REYMENT（1955）and WRIGHT（1957）in regarding 170γγθ8亡捌αas distinc七 from Bαγγoi8Zcθγα80n account of the presence of prominent mediolateral tuber－ cles in at least early to middle growth－stages． It is a fairly comprehensive and variable genus， comprising at leas七七hree subgenera， i．e． Foγγθs¢θ万α （s．s．）， Rθθ8掘θ06θγα8BAssE，1947， and a new one（1∬ZLγαγη0τ0α）to be established below． Z祝？ηPαγzgo6θγ・α8 BAssE，1947， could also be included in 1アoγγθ8τθ仇αas a subgenus， but I have no positive comments on this subgenus， which was established on crushed specimens from the Coniacian of Mexico（BuRcKHARDT，1919， pp．99－ 108；pl．22， fig．16；pl．23， figs．1－2；pls．24 and 25）． I should furthermore in－ clude E（1θη06θγα8 vAN HoEpEN，1968（with type－species E．阻μ1比os£α加仇vAN HoEPEN，1968）in Foγγθ8¢θγ乞αas a subgenus． Hαγ1θ乞εθ8REEsIDE，1932， with which AI8¢α∂例伽s REEslDE，1932， is syno－ nymous（WRIGHT，1957， p． L434；BAssE，1947， p．137）， is treated in this paper as an independent genus for the reasons described in another page （see genus

Hαγ1θ乞τθ8）． The type－species of Foγγθ8£θγZα， F．∫oγγθ8τθγZ REEsIDE，1932， is identical with ∠46α励んocθγα8 （PγZOη0加0廊） α1伽αμd冤BoULE， LEMoINE and THEVENIN， 1907，as is discussed below． VAN HoEPEN（1955， P．361）established Colligηo励一 cθγα80n the type－species C．んα抗抗θγ81θψvAN HoEPEN，1955． This generic name was subsequently renamed by vAN HoEpEN（1957）as CoZ吻πoηθIIα， as he noticed that Coll‘gηo励cθγαs vAN HoEpEN，1955， is a homonym of and preoccupied by Co膓1乞9ηo励oθγα8 BREIsTRoFFER，1947． Co～ZZgηoηθIZαvAN HoEPEN，1957， is， how－ ever， a synonym of Foγγθ8£θγτα， because C．〃α仇働¢γ81θ班and other species which vAN HoEPEN assigned to Col吻ηoηθZIαare all good examples of Foγγθ8τθ励α， as vAN HoEPEN（1968）himself has recently acknowledged． Species of F「oγゲθ8fθ万αoccur in the Coniacian of various regions， some of which show world－wide distribution．

Subgenus Foγγθ8¢θ弼αREEsIDE，1932

1～θ仇α袖s．－F「．（F．）αIZ％αzL碗 （BouLE，1・EMoINE and THEvENIN）， the type－ species， represents generalized or average characters of Foγγθ8£θがα， showing 蛤ther a gradual change of ornament with growth． More depressed and strongly 七uberculate species as 1汀．γαzαガ励Pαγαη糎Col・1・IGNoN，1965， and F． rθ〃働θ励づVAN HoEpEN，1968（the two of which are closely allied to each other and could be identical）， are included in 170γγθ8Zθγτα （s．s．）． In F．んobso励（REEsIDE，1932）the mediolateral tubercle is shifted upward and united with the large， horn－like ventrolateral tubercle on the adult whorl． 308 T．MATSUMOTO

Iwould regard this charac七er as specific rather than generic， since such a feature does not necessarily occur in other species of Foγγθ8君θγZα． The subgenus、Foγγθ8£θγZαcomprises also less depressed but distinctly tuber－ culate species， such as、P．‘伽θbαθvAN HoEPEN，1968， and a new one（F「．αγ7ηατα） to be described below． The illustrated syntype of GαzL彦〃‘θγ‘6θγα8γηαγ9αθ var． Z）θγτ↓αγzμγ7z BRUGGEN （1910，p．720， pl．27，6g．3）and the 6nely illustrated specimen of L、むTHY（1918， p．41，pl．1，6g．2）， from the Coniacian of Peru， probably represent another species of rather compressed Foγγθ8τθ冗α， as is F．（17．）bα88θαθBENAvIDEs－ CAcEREs（1956， p．477， pl．58， fig．5）． They seem to be identical and should be called Foγγθ8舌θ？イα （Floγγθ8τθηα）Pθγμαγ梛伽 （1効GGEN）．

Some of the less depressed species such as 17．8亡α批o励（REEsIDE，1932）and F．ρπα1θη8乞8（STEINMANN，1897），11ave a modified ornament on the outer whorl， on which mediolateral tubercles are absorbed by raised ribs． This subgroup can be， in my opinion， grouped with the subgenus E∂梛ooθγα8， because on the outer whorl of E．勿％IZτ608fα九物vAN HoEPEN（1986， P．171， pl．12， text－fig．4b）， the mediolateral and also the umbilica1七ubercles are likewise absorbed by thick ribs． Secondary， shorter ribs are more frequently intercalated in E．物視1飽08Zα加祝， but this is probably a specific character．

The subgenus IZθθ8‘d！θooθグαs BAssE，1947， has Iess infla七ed flanks and its mediolateral tubercles fuses with the umbilical one oll the outer whorl． Its type－ species is∠Lηz伽o？zπθ8 Pθ¢γ060冗θγz8乞8 CoQuAND （1859， P．995；DE GRossouvRE， 1894，p1．2， fig．5）． Rθθ8乞∂θ06θγα8 gαIIZcτ〃7z BAssE，1947， is an unnecessary specific name， because it is synonymous with Foγγθ8¢θγZα（Rθθ8掘θo¢θγα8）Pθ亡γocoγ乞θη8‘8． In this subgenus the keel disappears on the outer whorl， on which七he venter is flat or concave， bordered by ventrolateral clavi．

The world－wide species F．（F．）αZZμα閲ゼis found in Hokkaido． In addition to it there is another remarkable new species of Foγγθ8¢θγZα（s．s．）in the collec－ tions from Hokkaido． No examples of、Foγγθ8¢eγZα （Rθθ8Z∂θocθγα8）and F．（E∂θη06θγα8）have been found in Hokkaido， but there are two species of a new subgenus， which are characterized by a smoothed outer whorl．

Foγγes亡θ働（1汀0γγ¢8亡θ甑）α1玩α砿乞 （BOULE，1・EMOINE and THEVENIN，1907） Pl．40 ［28］， Figs．1－4；Text－figs．5－7

1907． A¢α励ん06θγα8 （Pηoηo¢γoが8） αZZμαz¢砺 BouLE， LEMoINE and THEvENIN， ／1γzγz．PαZεo？zε．， vo1．2， P．12 ［32］， pl．1 ［8］，6gs．6，6a，7， text－69．17． 1908． P励oγ↓oぴoが8α1抗αμ（ガ，LISsoN， Sobγθαlg祝η08醐伽πo痂亡θ8（1θZ Pθγz↓， P．17， pl．17． 1910． Pγτoηoγo傾8αZZτLαzL砺， BR廿GGEN，2V．」．ハZ仇． BθゼZ． Bd．30， p．772． 1932． Bα勿γoi8τ¢θγα8（Fo”θ8Zθγiα）αIZαμ碗［8司，REESIDE， U． S． GθoZ． S蹴η． Pγo∫． Pαρθγ170－B，p．14． 1932． BαγγoZ8τ¢θγα8 （Foγグθ8¢θ万α）∫oγγθ8舌θηREESIDE，σ．8． GθoZ． Sμγ〃． Pγo∫． Pαpθ170－B，p．17， p1．5， figs．2－7． AMonograph of the Collignoniceratidae from Hokkaido． Part III 309

1947． Bαγγoゼ8乞cθγα8 （F「0γγθ8¢θγτα）αZZμαμ（li， BAssE，∠4γτγτ． Pα160ηム， vol．33， p．128 ［32］，pl．8，6g．3，3a；pl．9， fig．2，2a （？）． ？1955． CoZI汐ηo痂cθγα8 Pθ7心θ9γiηαεoγvAN HoEPEN， So励んAρ． Jo耽． S6τ．， Vo1．51， p．364，text－figs．10－11． 1956． Bαγγoi8τcθγα8 （F・oγγ、θ8¢θγiα） αZZ視ατLd冤， BENAvIDEs－C五cREREs， BμII’ノ1仇θγ’ 1μμ8．Nα¢． Hτ8亡．， vol．108， P．478， P1．61， fig．1． 1965． Foγγθ8亡θ冗α αIZ視α視（江， CoLLIGNoN，1965， A¢1α8 Fo88τ1θ8 Cαγα6¢θγ． Mα∂α一 gα8cαγ， fasc．13， p．76， p1．448， fig．1828．

「 ’ ，’、 （

｝ 10mm 5 70 10mm 一 一

、≡＿ノ

人 ） ＼，ノ6 ’．ノ㌃＝ 7b

Figs．5－7． Foγγθ8¢θパα（Fo宵θ8¢θ万α）αIZz↓肌6砺（BouLE， LEMoINE and THEVENIN）．

Whor1－sections in various growth－stage．s and an e．xternal suture of an immature shell．5：GI（． H5442，6：GI（． H5440， 7：GK． H5441b． （T． M．∂θ1仇．）

丁脚θs．－BouLE et al．（1907）did not designate the holotype． Of the two illustrated syntypes， the larger one（BouLE et al．，1907， pl．1， fig．6，6a）is some－ what malformed in that the ventral row of tubercles deviates from the siphonaI Iine． The smaller one（BouLE et al．，1907， pl．1， fig．7；七ext一盒g．17）may be be七ter preserved， but the authors did not illustrate its side view． Therefore， Ihesitate to designate the lectotype without seeing the specimens， although they are certainly of identical species． Mαεθγ乞α1．－The following six specimens from the Ikushumbets area are referred七〇this species：（1）GK． H5442（T． MuRAMoTo Coll．2156），from Gono－ sawa， Pombets，（2）GK． H5440（T． MuRAMoTo Col1．914）， from a pebble of the Ikushumbets at Yayoi，（3）GK． H5441（T． MuRAMoTo Coll．）， from another pebble of the Ikushumbets at Yayoi，（4）GK． H5464（T． MuRAMoTo Coll． P5－ 2451），from Gono－sawa， Pombets，（5）GK． H5622 （H． KoKuBu Coll．）， from Ik 2119 p， Gono－sawa Pombets， and（6）GK． H5623（T． TAKAHAsHI Coll．36613）， from Ik 2147 p， Gono－sawa， Pombets． Spθ¢碗¢砺αgη08Z8．－A species of 170γγθ8亡θがα（s．s．）which has a moderately stout shell， moderately distant and coarse， radial ribs， and distinct tubercles， of which the mediolateral ones are the most prominent． Sutures are moderately 310 T．MATSUMOTO

incised， having Iateral saddles of roughly subrectangular outline and fairly narrOW lateral lObeS．

1レfθα8ZLγθγηθγ乙診8．一 Number of Specimen Diameter Umbilicus Height Breadth BりH． major ribs per whorI GK． H5622（c） 40．5（1） 9．2（．23） 20．4（．50） 25．0（．61） 1．22 11 （十10°）（ic） 40．5（1） 9．2（．23） 20．0（．49） 22．0（．54） 1．10 一 （－180°）（c） 13．5 17．3 1．28 一 （－190°）（ic） 12．7 一 13．0 1．02 GK． H5623（c） 23．7（1） 5．6（．23） 11．7（．49） 13．8（．58） 1．17 12 （－10°）（ic） 22．4（1） 5．2（．23） 11．2（．50） 11．2（．50） 1．00 一 （－180°）（c） 7．2 7．2 1．00 一 （－190°）（ic） 6．6 6．3 0．95 一 寸⊥噌⊥9一∩δ GK． H5440（c） 29．0（1） 8．2（．28） 12．8（．44） 17．06（．58） 0 0 50r 6×2 1⊥ （＋10°）（ic） 11．8 14．0 一 コ GK．且5442（c） ～57 ～16（．28） ～27（．48） ～33（．58） ～1．2 14（15？） COLLIGNON， 1965，p．76 81 25（．31） 37（．46） 50（．62） 1．35 For comparison F．∫o”θ8舌θ碗 ～50（c） 25（．5） 33（．6） 1．2 10（？） （REEgIDE， ～50（ic） 25（．5） 25（．5） 1．0 （‘‘1／4－1／3，，） 1932，p．17） 28（c） 13（．46） 16（．57） 1．2 10 14 6（．43） 4．5（．32） 0．75

the same 1⊥ ・ 9一ハU （p1．5， f．2－4） 26．5（c） 5．9（．22） 13（．49） 1 3ρ 寸⊥｛⊥ 4 10

O （ic） 13 ピ 0 コ C．Pθγθ9γ仇αεoγ （HOEPEN，1955， p．364） 75（1） 20（．27） 36（．48） 45（．60） 1．25 11（？）

Z）θ8励p励θγθ勿α祐8．－The specimens from Hokkaido show characters of various growth－stages． GI（．且5442 is nearly as large as the large syntype of BouLE et al．， while GK． H5622 is slightly larger than their smaller syntype and slightly smaller than BAssE，s（1947， pl．14［8］，毎．3）specimen． GI（． H5623 is asmall shell， representing the stage immediately preceding七〇tha七〇f GK． H5622． Other three specimens are as Iarge as one of七he above three and show apart of still inner whorls， although they are more or Iess defective． The speci－ men illustrated by CoLLIGNoN（1965， pl．448，丘g．1828）is七he Iargest but still wholly septate． One of BRUGGEN’s（1910， p．722）specimens， from Peru， seems to be as Iarge as Co肌IGNoN’s from Madagascar， although I have not seen it． No example as large as C旺LIGNo．N’s has been obtained from Hokkaido， although GI（． H5442， which preserves a portion of the body－whorl， may have been similarly large when it was complete． Summarizing the observation of these specimens as well as other previously described ones， it may be stated that the present species shows a rather gradual change of characters with growth． The specific diagnosis described above con－ cerns primarily with the shells of later growth－s七ages． There are， furthermore， minor dif［erences between individuals of the same growth－stage． AMonograph of the Collignoniceratidae from Hokkaido． Part III 311

The whorl grows with a moderate rate， embracing a little over a half of the inner one， with the umbilical seam just on the row of mediolateral七ubercles． The umbilicus is， accordingly， fairly narrow， ranging from one third to one fifth of the diameter of the entire shell． It is considerably deep． At 6rst the whorl is slightly higher than broad， having distinct ventrolateral shoulders and a keeled venter． A七the shell diameter of 20 mm． or so the whorI becomes broader， being as high as broad in the intercostal section and some－ what broader than high in the costal section（between tubercles）． In the later growth－stages it is slightly broader than high even in the intercostal section （wi七h b．／h．＝about 1．1）and collsiderably broad in the costal section （with b．／h．＝1．3±0．1）． The intercostal whorl－sec七ion is subrounded， with a steep umbilical wall， a rounded umbilical shoulder， moderately inflated flanks， and an arched but weakly keeled venter． Owing to the strong七uberculation the costal whorl－section looks polygonal． Ribs and tubercles begin to appear at abou七the shell diameter of 10 mm． In the early stage they are not so strong as in the later stages， especially the umbilical tubercles are undeveloped or indistinct， the mediolateral ones are of modera七e intensity， where ribs are normally bifurcated， and the ventral orna－ ments of the barroisiceratine type， consisting of three rows of clavate tubercles and rib8 in chevrons， are characteristic． In the later growth－stages the ribs are coarsened and the tubercles are strengthened． The mediolateral七ubercles are especially prominent， having a large base and a spinose apex． The umbilical tubercles are much smaller and of variable intensity． The ventrolateral tubercles are modera七ely strong， having abroader base than in the earlier growth－stage． The medioventral clavi persist to the adult stage， although the keel is lowered． Alow major rib runs radially from the umbilical margin to the mediolateral tubercle． The mode of bifurcation of the ribs at the mediolateral tubercles may vary with individuals or from place to place even in one specimen． Typica11y one secondary rib is projec七ed forward and the other runs almost radially on the extension of the major one． Sometimes Y shaped branching is shown． Occa－ sionally the intercalation of the secondary rib is seen at one place， while the simple extension of the major rib is seen at another． As far as the measurable specimens are concerned， there are 10 to 12 major ribs in a whorl． GK． H5442 may be exceptional in that its septate whorl has somewhat more crowded and more numerous（14）ribs， but on its body－whorI the rib8 are as distant as in normal specimens． On七he other hand the holotype of BαγγoZ866θγα8 （Foγγθ8¢θ仇α） ∫oγ？楡θ8古θγZ REEsIDE （1932， P．17， pl．5，69．2－7）， NSNM．73757， has 10 major ribs per whorl and the ribs on七he outer whorl seem to be somewhat more distant than those on the syntypes of F．α伽α偏τ． The dif［erence is by no means great and can well be included within the varia－ tion of．F．（1P．）α批α城Z． As the available specimens from North America are few， it is not decided at this moment whether a subspeci丘c separation is possible or not be七ween the North American and Madagascar groups of individuals． It is interesting to note that some of the specimens from Hokkaido（e．g． 312 T．MATSUMOTO

GK． H5442， H5622 and H5623）are closer to the syntypes of、F．（F．）αZIματL（況 from Madagascar and some others（e．g． GK． H5440 and H5441）are rather similar to the holotype of F．∫oγγθ8亡θγ¢from North America． The latter subgroup has slightly more distan七ribs and better marked umbilical七ubercles in somewhat earlier growth stage than the former， but the difference is slight and there is gradation between the two subgroups． In other words it is natural and reasonable 七〇refer the Hokkaido specimens to one and七he same species which in itself shows a moderate（but not great）extent of variation． BENAvlDEs－CAcEREs （1956， P．479）stated that F．αIIμαμ〔IZ and 17．∫oγγθsτθが were separable only by the spinose character of the ornamentation in the latter species． This is， in my observation， merely a problem of preservation． GK H5622， for instance， does show the spinose mediolateral tubercle on a well preserved part but the spine is septate and only the basal rounded nodes are shown on other parts of the same specimen． Taking all the above observations in七〇consideration， I am led七〇the con－ clusion that Foγθ8亡θγ乞αプoηθ8¢θが（REEsIDE，1932）falls in the synonym of Foγグθ8舌θがαα1ψαμ碗（BouLE，1・EMoINE and THEvENIN，1907）． Even if the sub－ specific separation could be considered， the specific nameα伽α煽Z should precede

∫oゲγθ8¢θγ6．

CoII乞9γzoγzi¢θrα8 pθγθgがηα¢oγvAN 且oEPEN，1955， （p．364， text－figs．10－11）， from South Africa， is possibly identical with F．α1伽α城Z， because of the similarity in every respect． VAN HoEpEN（1968， p．167）has recen七ly regarded F．PθγθgZ％α加γas iden七ical with、P．んα仇仇θγ8Z¢〃Z vAN HoEPEN，1955． Should this be accepted， then it would follow that the Iarge holotype of F．んα働㎜θγ81θψ （vAN HoEPEN，1955， p．361， text－6gs．7－9），from Sou七h Africa， with a diameter over 220 mm．， would represent七he fu11－grown stage of 17．α1勧α煽i． I refrain from giving the final conclusion， until I can examine relevant specimens from South Africa and Madagascar．

Aminor but interesting malformed fea七ure is occasionally observable in the available specimens． On七he last one third of the whorl of GK． H5623， the medioventral row of tubercles deviates from the siphonal line， resulting in unequal distance from the row of ventrolateral tubercles on either side． The same feature is seen on one of the syntypes of Bo肌E et al．（1907， p1．1［8］， 毎．6a）． Co伽Pαγ‘80π．－F’oγγθ8£θηα（Fo御θ8τθγZα）αII祝α2雄most typically represents the sul）genus Foγγθ8τθγταin that it shows the subgeneric characters in a general way and in a moderate degree． It is not so compressed as F．8θ砂iθγθη8θ （REEsIDE） （1932， p．16， pl．4， figs．4－8）nor is it so depressed as 1汀．γαzαガ厄一 Pαγα？zψCol、ロGNoN（1965， P．78， pl．449， figs．1829－1831）． Its ribs and tubercles are regularly disposed and rather gradually strengthened with growth． In this species there is no hypernodosity nor shift of tubercles as in F・ んob80？zゼ （］REEslDE） （1932， P．18， P1．9， figs．1－2， pl．10， figs．1－2）， nor fusing of la七eral tubercles into sharp ribs as in 17．8¢α励o仇 （REEsIDE） （1932， p．17， pl．7， figs． 1－7；pl．8，6gs．1 3；pl．9， fig．1）． AMonograph of the Collignoniceratidae from Hokkaido． Part III 313

Foγγθ8εθγ乞αcf．αZIα掘乞［sic］of PARNEs（1964， p．23， pl．2， figs．7－8）， from Israel， which has compressed whorls and somewhat upward shifting lateral tubercles， is probably distinct from F．α批α掘τ， unless the compression owes to secondary deformation． It may be closer to， if not identical wi七h， Foγγθ8fθγiα bα88θαθ （BENAvlDEs－CAcEREs） （1956， P．477， pl．58， fig．5） ［＝Bαγγoぜ8乞cθγα8 んαbθγ∫θZIηθγZ， BRむGGEN，1910，印oηHAuER），P．730， text－fig．10］［＝Bαγo乞88i¢杉γα8 λαbθヅθIIηθγτ， ST．EINMANN，1930， text－fig．195］， from Peru， or、F． Pθ閲α批抗 （B前GGEN），emend． Foγγθ8亡θγ掘（Foγγθ8亡e万α）わ仇αssαi（VENzo）（1936， P．88， pl．7［3］， fig．12； text－fig．1）from Zululand， South Africa， closely resembles F，（F．）α批α閲ゼ， but has stronger ribs． In the latter species the tubercles are rather prominent over ribs． 066祝γγθη¢θ．－Gono－sawa， Pombets， a tributary of the Ikushumbets， zone of 加ocθγα仇祝8祝ωα元伽θη8乞8；pebbles of the main course of the Ikushumbets， at Yayoi， together with 1ηocεγα仇μ8〃o〃o〃α仇α乞NAGAo and MATsuMoTo． Summariz－ ing these records of occurrence in central Hokkaido， the species seems to occur in the main or middle part of the Lower Urakawan［＝approximately Coniacian］ in the Japanese scale． Foγγθ8亡θγ乞α（、Foγγθ8εθγ乞α）αZ抗α癩乞seems to show a world－wide distribution in the Coniacian， since there are available records of its occurrence in Madagas－ car， South Africa， Peru， Utah（U．S．A．）and Japan． In Madagascar， according to Col．LIGNoN （1965）， it occurs in the zone ofκ088祝αε乞¢θγα8 仇θobα1〔1乞α？z視仇一 BαγγoZ8τcθγα8 0励Zα々θη8θ， Middle Coniacian． In South Africa vAN HoEPEN reported the occurrence of 、P． pθγθgγ仇αfoγ from his 1）θγoη乞¢θγα8 beds （Coniacian）．

Foγγθ8¢θγZα （Foγγθ8¢θγ乞α） αクη7ταεα sp． nov．

Pl．41［29］，Fig．1；Text－fig．8

Holo切pθ．－GK． H5621， from loc． Ik 2144p， Gono－sawa， Pombets（Coll． T． TAKAHAsHI 42－10－1－1）． Spθc頒c∂乞αgη08τ8．－A species of Foγγ・θ8εθγ乞α（．Foγγθ8εθ万α）which has com－ paratively higher whorls， less inflated flanks， rather prorsiradiate ribs and prominent mediolateral tubercles． The umbilical tubercles are indistinct and the ventral ones are of moderate intensity． On the body－whorl the ribs are much separated and the mediolateral tubercles become bullate and sharp－headed． The first lateral lol）e of the adult suture is narrow and deep．

1レfθα8τLγθγηθγzτ8．一

GK． H5621 Diameter UmbiliCUS Height Breadth B．／H． at the last 82．0（1） 24．6（．30） 40．0（．49） 26．0（．32） nbOV← septum（ic） ● 08

behind （c） 34．2 33．6 ■ 一

Dθ8cγ⑳物θγθ仇αγ〃8．－Only a single specimen is before me and its body一 whorl is crushed， but the observable characters are distinct． 314 T．MATSUMOTO

Fig．8． Foハ・γ杉8亡杉7’τααηηα亡αsp． nov．

GK． H5621， holotype． Lateral view showing sutures（the same view as Pl．41， Fig．1a under different light）． （1． HAYAMI photo）

The whorl is moderately involute， increasing fairly rapidly． The umbilical seam is just above the row of mediolateral tubercles of the inner whorl． The umbilical wall is steep， nearly vertical or even overhanging and the umbilical shoulder is abruptly rounded． The flanks of the whorl are only gently inflated and the whorl is higher than broad in the intercostal section， being broadest at the middle of the flank． The ribs are more or less prorsiradiate and slightly concave from the um－ bilical margin to the middle of the flank． They are separated by somewhat wider interspaces， being counted as much as 15 to 16 per whorl in the phragmo－ cone， although the shell of early stage of less than 10 mm． diameter seems to be smoothish． They are moderately strong． Some of them have bullate umbilical tubercles， but some others are almost free from the umbilical bullae and occa－ sionally weakened near the umbilical margin． The mediolateral tubercles are prominent on the inner whorl， stretching laterally along the vertical umbilical wall of the outer whorl． On the outer half of the last whorl of the phragmocone， some of the mediolateral tubercles are large and rounded but others are less strong and somewhat bullate． The ribs are usually bifしlrcated at the mediolateral tubercles． The ventro一 AMonograph of the Collignoniceratidae from Hokkaido． Part III 315

1ateral tubercls are， accordingly， twice as numerous as the mediolateral ones． They are of moderate intensity and somewhat obliquely clavate， extending to projected weak， ventral ribs． The medioventral tubercles are clavate， each of which is placed considerably forward of the ventrolateral tubercle． They are aligned on a keel． On the adult body－whorl the ribs are distant， being separated by very wide interspaces． They are low and prorsiradiate up to the middle of七he Hank． The umbilical tubercles are faint or obsolete． The mediolateral tubercles are much elevated， with a broad base and a narrow but sharp summit which are elongated obliquely forward． The secondary ribs which should run in pairs from the mediolateral tubercles are much weakened， broadened， and accordingly， indistinc七， while the ven七roIateraI tubercles persi8t as Iow cIavi． Owing to the incomplete preservation the character of the median－ventral part of the body－whorl is皿ot known． The suture is similar to that of Foγγθ8εθγ‘α（Foγγθ8εθ質α）αII肌μ砺， but the 五rst lateral lobe has a narrower stem and the lobules are generally deeper than in the latter． The folioles show somewhat phylloid aspects． Co仇PαγZ80η．－In the strong tubercles the present species is similar to Foγγθ8τ¢γ乞α （1アoγγθ8¢θがα）γαzαガ励Pαγα励CoLLIGNoN （1965， P．78， pl．449， figs． 1829－1831），from the middle Coniacian of Madagascar， but is clearly dis－ tinguished by higher， instead of depressed， whorls， more slender and pror－ siradiate ribs and weaker or obsolete umbilical tubercles． In the Iess depressed whorls and prominent mediolateral tubercles F．（F．） αγ勿α亡αis allied to F．（F．）πωθbαθvAN］旺oEPEN （1968， P．169， pl．10， text－fig． 3c）from the Coniacian of South Africa， but is distinguished in its radially elongated， sharp－headed mediolateral tubercles on the outer whor1， somewhat prorsiradiate ribs， and broader umbilicus． In the less inflated flanks with slender and prorsiradiate ribs， the present species is somewhat similar to F「oγγθ8ε碗α （E∂θηo¢θγαs）獅£α1θηsZ8 （STEIN－ MANN） （仇GERHARDT，1897， p．198， pl．5， fig．21） （also BAssE，1947， p．130， pl．13［7］，丘g．4）， from the Coniacian Pγゼoη06〃c乙ocθγαs g祝靱αbα協祝bearing bed of Colombia， and also to F．（1D〔1θηOCθγα8）8τα励oM REEsIDE（1932， p．17， pL 7，6gs．1－7；pL 8，五gs．1－3；pl．9，丘g．1）， from the Frontier Formation of Wyoming， U． S． A． In our species the mediolateral tubercles are very prominent at the middle growth－stage and persist onto the adult body－whor1， being pre－ dominant over the ribs． In the two species from the Americas the mediolateral tubercles tend to be absorbed by七he sharpened radial ribs on the outer whorl． The umbilical tubercles are fairly distinct in F．（E．）8舌α励o励． Occμ”θηcθ．－Loc． Ik 2144p， Gono－sawa， Pombets， zone of 1η06θγα批μ8％ψα一 グ伽zθγτ8τ8，Coniacian．

SubgenUS 」Mμ7・α7η0ε0αnOV．

S卿o％y仇y．－8α88θo¢θγα8vAN HoEPEN，1968伍oηCo肌IGNoN，1965）・ E勿伽olo9〃．－Dedicated to Mr． Tatsuo MuRAMoTo， who has contributed much 316 T．MATSUMOTO in collecting numerous， valuable specimens of ammonite8 from Hokkaido． T〃2）θ一8Pθcτθ8．－170γγθ8¢θγ‘α （2∬z〃αγηoτoα） 2ノθzoθ？τ8Z8 sp． nov．， to be described belOW． Gθηθγぜo碗αgη08乞8．－The whorl is moderately involute， with a fairly narrow umbilicus． It is somewhat higher七han broad at least in the adul七stage and has rather gently inflated Hanks． In the early to middle growth－stages ribs and tubercles are distillc七． The mediolateral tubercles are the strongest and do not fuse with ventrolateral nor with umbilical tubercles． In the late growth－s七ages the ribs and tubercles are weakened and typically the shell becomes smoothish， with a faint， unserrated ventral keel as an extended trace of the row of ventral clavi． The suture is fundamentally of the same type as that of Foγθ8古θγZα（Foγ一 γθ8‘θηα）．In the adult stage it has a comparatively deeper lateral Iobe（L）and deeper lobules of the external saddles． 1～θγηαγん8．－In addition to the type－species， Foγγes£杉γτα （Mμγα糀o£oα） 〃θzoθπ8Z8， another new species to be described below， and Bα”o緬6θγα8（170γ一 γθ8Zθがα）αηzp成αZoα〃αθ％8θBAssE，1947， are referred to the subgenus Mτ〃αηzo¢oα． Bα88θooθγα8抗α仇θγτVAN HoEPEN（1968， P．164， text－figs．2b－9． pl．7），from the Coniacian of South Africa， has a Foγγθ8舌θ傾α（s．s．）Iike immature shell and afeebly ornamented adult whorl． No photograph of the holotype（Z935）was shown by vAN HoEpEN， but its plaster cas七has been kindly sent to me from the Geological Survey of tlle Republic of Sou七h Africa． It is larger， about 107 mm． in diame七er， and has much weaker ornament than the illus七rated para七ype （Z1437）． On the earlier half of the outer whorl of the holotype weak medio－ lateral tubercles are discernible in addition to the umbilical， ventrola七eral and ventral ones of moderate intensity． On the later half of the outer whorl， which is still septate， the mediolateral tubercles and the ribs disappear， the umbilical and ventrola七eral七ubercles are much weakened， the keel is・lowered and the ventral clavi on the keel persist for a somewhat longer period than others but 6nally七end to disappear． In fact the South African species is fairly close to 170γゲθ8¢θγ6α （1吻γα仇oεoα） α仇pozαZoα〃θws乞8 from Madagascar． Bα88θocθγα8 〃γα？ηθがis， thus， referred to the above defined subgenus 2∬μγαγηo渉oα． Bα88θ06θγα8伽α物θγZwas designated as the type－species of Bα88θooθγα8 vAN HOEPEN，1968． I agree with vAN HoEPEN in regarding this species group as a new taxon．且owever， Bα88θ06θγα8 vAN HoEPEN，1968， is a homonym of and preoccupied by Bα88θocθγα8 Co肌IGNoN，1965． We should use the subgeneric name M耽α仇o¢oα for this species group， since B．ψα魏杉γZ is referred to

Mμγα仇o毒oα． Co物Pαγ‘80ηα煽α茄M句．－1吻γα？ηo加αresembles a relatively compressed species group of Foγγθ8τθゲZα（s．s．）especially in immature stages， but is dis－ tinguished by its weakening and final disappearance of the ornament in the adult whorl． They are not so much separated from each other that the subgeneric separation is adequate． Some species of 170”θ8／θγZα（1POγγθ8亡θWlα）have more inflated whorls on which tubercles are generally strengthened or exaggerated． In the less inflated shell it is somewhat similar to Foγγθ8τθ冗α（Rθθ8砿θo． AMonograph of the Collignoniceratidae from Hokkaido． Part III 317

¢θγα8）especially in the immature stages． On the outer whorl of the latter sub－ genus the mediolateral tubercles are uni七ed with the umbilical ones， the keel disapPears and the venter becomes flat or concave instead of roof－shaped． In the attenuation of the ornament、Foγγθ8舵γZα（1∬％γα勿o¢oα）is allied七〇 Solgθγ舵8 REEsIDE，1932． In the immature stages of the former the Fo搾θ8¢θがα type general characters are bet七er re七ained， whereas the latter is so specialized that it considerably deviates from Foγγθ8亡励αas seen by the flattened shell－form and fine， dense ornaments even in the imma七ure stages． Mμγα仇o£oαis super丘cially similar to Bα88θo¢θγαs CoLLIGNoN，1965 （see p．3010f this paper）in the smoothish outer whorl． In七he earlier growth－stages the distinction is unmistakable， since the former has the same type of characters as七ha七〇f immature Foγγθ8£θγ6α（s．s．）， having distinct mediolateral tubercles， and the Iatter has essentially the same type of characters as that of BαγγoZ8‘6θγα8 （s．s．）． The upward shifted umbilical tubercles on the outer whorl of Bαγγo‘sτ一 6θγα8 （Bα88θ06θγα8）60Z6耽α餌CoLLIGNoN，1965， do llot correspond with the independent mediolateral tubercles of F．（Zレfz¢γαγηoZOα）γθ20θη8τ8 and other species of F． （M2↓γα？7ZO古0α）．

Foγ¢8‡θ蜘（1吻γ蹴o亡oα）翌e20飢8乞8 sp． nov． P1．42［30］， Figs．1－2；Text－figs．9－10

Mα¢θ碗αZ．－Holotype， GK． H5462， from loc．2155p1， Gono－sawa， Pombets， zone of 17zo6θγα仇μ8μψαグゼ物θ？z8Z8， collected by T． MuRAMoTo． Paratypes， GK． H5463［＝T． MuRAMoTo’8 coll． no． P5－6323］and GK． H5557［＝T． TAKAHAsHI’s coll． no．41－6－1．1］， from Gono－sawa， Pombets．

Fig．9． FoγγθS¢θパα（刀1μγαγη0¢0α） 〃θZOθγt8i8

sp・nov・

GK． H5462， holotype． Diagrammatic whor1－section． （T．M．（1θliη．） 20mm 318 T．MATSUMOTO

u3（＝s） ε

5鼎鴨

Fig．10． Foγ㌍θ8¢θ7’iα（11Zμγα7ηoεoα）〃θzoθπ8τ8 sp． nov．

External suture of the holotype， GK． H5462， at h＝25．5 mm． （T．M．（1θZ仇．）

8pθo切6¢〃αγα¢¢θγ8．－The whorl is moderately involute， embracing a fairly narrow umbilicus． It is higher than broad， having a proportion of 10：8．5 between height and breadth． The umbilical wall is rather low and nearly vertical or slightly overhanging． The umbilical shoulder is abruptly rounded． The Hanks are only gently convex or nearly flat and gradually convergent， form rather blunt ventrola七eral shoulders and then pass to a low roof－shaped venter． The whorl is broadest at about the lower one third of the height． The ventral keeI is lOW． The immature shell， up to the diameter of 400r 45 mm．， is ornamented with tubercles and radial ribs of moderate intensity． The mediolateral tubercles are七he most predominant on the whorl of the middle growth－stage（diameters from 25 to 40 mm．）， being situated at the umbilical seam of the outer whorl， whereas the umbilical tubercles are small or indistinct， being sometimes dis－ cernible only as slight angulation of the radial ribs at the umbilical shoulder． The ribs are rectiradiate， moderately strong and separated by somewhat wider interspaces on the inner part of the Hank from the umbilical shoulder to the mediolateral tubercle． Then they are bifurcated there or inser七ed a七al）out the same level． Some of the bifurcated or inserted ribs are prorsiradiate． The secondary ribs are somewhat weaker than the major ones． The ventrolateral tubercles are of moderate intensity in the immature stages and about twice（or slightly less than twice）as numerous as the mediolateral ones． The lowered ribs are projected from the ventrolateral tubercles to the ventral clavi， forming chevrons on the venter． The ventral clavi are at 6rst moderately strong， giving distinct serration on the keel， but in the middle growth－stage七hey are already weakened and the serration on the keel becomes less distinct． In the late growth－stage， i．e． from the Iast part of the septate whorl to the adult body－whorl， all the ornaments are sooner or later weakened and finally disappear． In the holotype the ventrolateral tubercles are gradually weakened and perslst to a sllghtly Iater stage than the rapldly weakened medlolateral ones， AMonograph of the Collignoniceratidae from Hokkaido． Part III 319 but they finally disappear and only blunt ventrolateral shoulders remain． The ventral keel persists for the longest period， but i七is lowered and becomes smooth， as its serration is lost． The su七ure in the late growth－stage is comparatively deeply incised than other species of Foγγθ8亡θゲτα． The two lobules which subdivide the head of the 6rst lateral saddle （between E and L）are fairly deep and a lobule which asymmetrically divides the second lateral saddle（between L and U2）is very deep． The first lateral lobe（L）is the deepest and much deeper than broad， being asymmetrically bipartite， having four， fairly deep lobules in the lower part． The second lateral lobe（U2）is about a half of L in size． Three o七her， smaller， auxiliary lobes are discernible in the external suture．

1κ杉α8ZLγθ？ηθ7乙z8．－ Specimen Diameter Umbilicus Height Breadth B．／H． GKH5462 73．3（1） 17。7（，24） 35．6（．49） 30．3（．41） 0．85 GK． H5463 20．5（1） 3．6（．17） 11．2（．54） 9．2（．45） 0．82 GI（． H5557 55．0 10．5（．19） 27．5（．5） 19 0．7 （secondarily compressed）

Rθ勿αγ〃8．－Although the three specimens before me are not quite identical， Iregard them as one and the same species． Minor differences are probably due to difference with growth－s七ages as well as to variation． The shell seems to be more involu七e and more narrowly umbilicate in earlier growth－stages． The ribs and the tubercles are coarser in the middle growth－ stage than in the earlier ones． Co勿pαγ‘80η．－III the comparatively compressed whorl七he immature shell of the present species resembles that of F「oゲγθ8¢θγτα （170γγθ8亡θγZα）8θ励γZθη8θ （REEslDE）（1932， p．16， pl．4， figs．4－8）， from the Mancos Shale of Utah， and 170γγθ8¢θγ乞α（170γγθ8τθγ乞α）bαs8θαθBENAvIDEs－CAsEREs（1956， p．477， pl．58， fig． 5） ［＝Bαγη08ゼcθγα8 1↓αbθげθII％θη， STEINMANN ⑰oη HAuER），1930， text－fig． 195］from the Coniacian of Peru． It is distinguished from the North American species by its somewhat finer ribs， more numerous ventrolateral and ventral tubercles， weaker or obsolete umbilical tubercles；from the Peruvian species by its stronger mediolateral tubercles which are situated at a longer distance from the ventrolateral tubercles and also by weaker or obsolete umbilical tubercles． The distinction in七he adult stage is unmistakable． The present species closely resembles Foγγθ8‡θ商α（刀f1↓Lγαγ〃01！0α）α仇pozαloα一 んθη8i8 （BAssE） （1947， P．131， pl．9， fig．4；also CoLLIGNoN，1965， P．80， pl．450， fig．1832），from the Coniacian of Madagascar， in both of which the attenuation of the ornament is characteristic． In the immature stages the latter has distinct umbilical tubercles． The major ribs alld the mediola七eral tubercles in七he middle growth－stage are stronger in the former than in the latter． Furthermore， the latter seems to have somewhat broader whorls七han the former．（BAssE，1947， did not record the measurements of the holotype． CoLHGNoN’s，1965， measure一 皿ents of another specimen give the proportion of breadth to height＝8．8：10．0）． Ocoμγγθη6杉．－Loc． Ik 2155pl and nearby localities in the stream called Gono－ sawa， Pombets， a tributary of the Ikushumbets， central且okkaido． All the 320 T．MATSUMOTO examined specimens came from the zone of 1η06θ夕α仇％8秘ωαブ乞働θη868， Coniacian， and were contained in calcareous nodules of fine－sandy siltstone． They are coated with black green， serpentine like matter．

Foγγθ8舌θγiα（1吻γ醐o¢oα）勿僻蹴o¢06 sp』ov． P1．43［31］，Fig．1；Text－figs．11

Mατθア‘α1．－Holotype， GK． H5620， from Ioc． Ik 2150p， Gono－sawa， Pombets （Coll． T． MuRAMoTo）． Paratype， T． TAI（AHAsHI’s collection from Gono－sawa， Pombe七s． 8pθc萌66〃αγαo渉θγ8．－The shell is rather small and fairly narrowly umbilicate， with a variable degree of involution of whorls． The umbilical wall is moderately high and overhanging． The umbilical shoulder is subangular to abruptly rounded． The immature whorl is less compressed than the adul七and has considerably convex flanks． It is somewhat higher than broad in the intercostal 8ec七ion but broader than high in the costal section， being broadest between the tubercles at about the lower one third of the height． The adult whorl is higher than broad and has gently inflated and rather convergent flanks． The ven七er forms a low roof shape， but the ventrolateral shoulder becomes blunt and then subrounded in the adult shell． A low ventral keel， which is distinct on the inner whorls， tends to disappear in the Iast part of the adult whorl． The mediolateral tubercles are comparatively large and strong on the inner whorls， ten or so per whorl． The umbilical tubercles are indistinct or un－ developed． The radial ribs which arise at the umbilical shoulder are broadened toward the mediolateral tubercles． The ventrolateral tubercles are small， some－ what clavate and numerous， being about three times as numerous as the medio一

b

20mm 一一 Fig．11． 170”θ8亡θパα（λZ2イ〃α？η0亡0α）仇μγα働oεo奄sp． nov．

Paratype， T． TAKAHAsHI Col1．， from Gono－sawa， Pombets． Latera1（a）and fronta1（b）views in ske．tch． （T． M．∂θ1仇．） AMonograph of the Collignoniceratidae from Hokkaido． Part III 321 lateral tubercles． The secondary ribs， which run from the mediolateral tubercles to the ventrolateral ones， are weak． They are bent somewhat forward on the venter． The ventral clavi are moderately distinct in the middle growth－stage and then weakened． On the adult body－whorl the mediolateral tubercles are gradually weakened， sooner or later suppressed to bullae that extend七〇blunt ribs， which， in turn， are still more weakened and finally disappear． The ventrolateral and ventral clavi and the secondary ribs are weakened and then disappear at a distinctly earlier growth－stage than the mediolateral tubercles． Consequently七he outer part of the body－whorl looks smoothish． On七he smoothish las七part of the body－ whorl faint lirae are discernible． They show a gently concave curvature on the main part of the flank and are gradually bent forward at the rounded ventro－ lateral shoulder． Sutures， though not well exposed， seem to be similar to those of．F．（ルf．）

〃θ20θη8τ8・

1μ’θα8ZLγθ？ηθη亡8．一

Specimen Diameter UmbiliCUS Height Breadth B．／H． GK． H5620 56．0（1） 10．2（．18） 30．0（．53） 24．0（．43） 0．80 ＿1／2vol． 17．9 16．0 0．88（ic） 16．4 18．4 1．12（c） Paratype 73．0（1） 20．7（．28） 35．5（．48） 29．0（．40） 0．81

R醐αγ〃8．－As is shown by the above measurements， the two examined speclmens are somewhat dissimilar in the relative width of umbilicus or in the degree of involution． This is takell here as variation and to some extent as a change with growth－stages as in the case of the preceding species． Co仇pαγ乞80η．－This species resembles Foηθ8τθγZα （1∬％グα勿o¢oα）〃θ加θη8Z8 sp． nov．（described above）， but is distinguished by more convex Hanks， more distant ribs， stronger and larger mediolateral tubercles， which persist to a later growth－stage， and comparatively more numerous and smaller ventrolateral tubercles． The immature shell of the present species is somewhat similar to that of Foηθ8¢θγゼα（Foγγθ8君θγ乞α）αIIμαμ〔IZ（BouLE， LEMoINE and THEvENIN） （see de－ scription in p．308）， although the distinction in七he adult shell is unmistakable． Even in the immature stage the two species can be distinguished in that the whorl is less depressed and the difference in intensity and density between the mediolateral and the ven七rolateral tubercles are more remarkable in F．（刀f．） 物耽α糀oτoτthan in 17．（F．）αIZμα履Z． Moreover， the umbilical tubercles are faint or undeveloped in the former， whereas they are distinct in the latter． The disposition of the ornaments in the middle to late growth－stages is some－ what similar to that of Foγγθ8¢θηα（Rθesτ（1θOCθ7・α8）pθか060γZθη8Z8（CoQuAND） （1859，P．995） ［＝17．（R）9αIZ60zL抗BASSE，1947， P．133］ ［＝BαγγoZ8i6θγα8んαbθゲー ∫θII？τθγ乞， GRossouvRE，1894印o？τ且AuER，1866）， Pγo Pαπθ， P．50， pl．1， figs．1－5； pl．2， figs．1，3，5］， from the℃oniacian of France． If the large specimen of GRossouvRE’s（1894），pl．1， fig．2is regarded as identical with CoQuAND’s holotype 322 T．MATSUMOTO

［＝GRossouvRE，1894， pl．2， ng．5］， it follows that the ornament is weakened also in the last part of the adult whorl of F．（R．）pθ加060γ‘θη8δ8． In F．（R．） pθ加oco冗θη8τ8七he mediolateral tubercles are united with the umbilical ones， resulting in bullate umbilical tubercles in a late growth－stage． In F．（M．） 勿微α仇o彦oZ the umbilical tubercles are indistillct from the beginning and the prominent mediolateral tubercles become bullate in a Iate growth－stage， still keeping their highest point a七about the mid－Hank． F．（M．）仇wαMo毒oi has a Iow， roof－shaped venter even in late growth－stages， whereas 17．（R．）p・θかo－ 60万θη868has a flat to concave venter in late growth－stages， in which the ventro－ lateral angulation is remarkable． I think Mμγαγηo加α and Rθθsi（1θ06θγα8 are fairly close to each other， as BAssE（1947， p．131）has already suggested with respect to F．（M．）α勿pozαloα一 〃θw8Z8． They are， however， considerably deviating from each other and七he subgeneric separation can be justified． Oc¢μγeηce．－Loc． Ik 2150p and a nearby locality in a stream called Gono－ sawa， Pombets， a tributary of the Ikushumbets， central Hokkaido． The two examined specimens came from the zone of 1ηocθゲα？耽8秘ωα∫Z仇θη8τ8， Coniacian， and were contained in calcareous nodules of 6ne－sandy siltstone． They are coated with black green matter．

Genus yαbθ乞cθγα8 ToKuNAGA and SHIMIzu，1926

S〃woγL（〃仇γ．－1Dboγocθγαs BAssE，1946． 欠〃Pθ一8Pθ¢Zθ8．一γαbθτ¢θγα80万θ励α1θToKuNAGA and SHIMIzu，1926（original designation）． Gθηθ万¢砺αgη08ゼ8．－The shell is moderately Iarge and widely umbilicate， consisting of evolute whorls which show a remarkable change in charac七ers with growth． The inner whorls are depressed to subrounded， with rounded umbilical shoulders， convex Hanks and a weakly keeled venter， and provided with distant radial ribs， strong mediolateral tubercles， numerous， weak， ven七rolateral elevations or tubercles and serrations on the keel． The umbilical tubercles may． or may not be present． The radial ribs are bifurcated at the lateral tubercles and， accordingly， the ventrolateral nodes on 七he projected secondary ribs are twice as皿merous as the lateral ones． The serrations on the keel correspond in number to the ventrolateral tubercles． In the next growth－stage， i．e． on the Iast second whorl， which is stilI broader than high or nearly as broad as high， the ventrolateral tubercles dis－ appear and the venter becomes smoothish， having only a blunt， smooth keel． The malor ribs and／or lateral tubercles remain in this stage， but are sooner or later weakened． In the full－grown stage， i．e． on the main part of the body whorl， the orna－ ment entirely disappears and even the ventral keel may be lost． The Iast whorl is typically， but not always， higher than broad， with less convex and more or less convergent flanks， subangular umbilical shoulders， and more or less rounded or sloping ventrolateral shoulders． AMonograph of the Collignoniceratidae from Hokkaido． Part III 323

The body－whorl is long， occupying nearly an entire outer whorl． At the final part it may be reduced in breadth and height． A constriction may mark the peristome． The suture， as clearly shown by the type－species， is similar to that of Foγγθ8£θγiα， but it may be somewhat more丘nely and deeply incised and may have a narrower first lateral saddle（between E and L）． 1～θγzαγ〃8．－In addition to the type－species ToKUNAGA and SHIMIzU （1926） described two other species， y．〃oτoねnd Y． M仇μγo乞， from the lower part of七he Futaba Flormation（Coniacian），Northeast Japan． 1Dboγ06θγα8糀αgηαμ仇b乞κ6α枷働BAssE（1946， p．73， pl．2， fig．2；text－fig．2）， from the Coniacian of Madagascar， is an example ofγαbθi6θγα8， fairly close toγ． oγiθ励α1θ， as was pointed out previously（MATSuMOTO et al．，1964， P．330）・ Consequently Eboγ06θγα8 BAssE，1946， falls in a synonym of Yαb杉乞cθγα8． This is accepted by Co肌IGNoN（1965），who added more interesting species of yαbθゼcθγα8 from the Coniacian of Madagascar． They are Y． bZ飢bθγ梛Zα¢μ仇CoLLIGNoN （1965，p．82， pl．451， fig．1836；pl．452， fig．1838）， Y．椛θηαbθη8θ CoLL、IGNoN （1965，P．86， pl．453， fig．1840）， Y． co8施施仇CoL・HGNoN （1965， P．87， pl．454， fig．1841）and Y．αη厄？zα¢8〃θη8θCoLLIGNoN（1965， P．87， pl．454， fig．1842）． The last species is atypical in that its whorl is less broad even in the septate stage and in that the lateral tubercles are absorbed by the major ribs． In y．608τα勧勿， which has broader whorls， the lateral tubercles are discernible in the earlier stages but are weakened and absorbed by the persistent major ribs． The holotypes of these two species are wholly septate and we need more specimens which represent the full－grown stage． The patterns of the sutures have no七been illustrated for some species from Madagascar and need further study in comparison with those of the type－species． Co勿pαγi80ηα嬬α伽物．－When I described， together with coworkers （MATsuMoTo et al．，1964），γαbθZ6θγα80がθ耐α1θToKuNAGA and SHIMIzu， from the lower part of the Futal）a Formation， I discussed to some extent about the afnnity of YαbθZ¢θγαs， but did not clearly decide its systematic position． Lines of evidence available at present allow us to conclude that it is bet七er to ascribe yαbθZcθγα8 to the Barroisiceratinae than to any other group． In the evolute and widely umbilicate shell yαbθ乞cθγα8 is atypical of the subfamily， but it is allied to．Foγγθ8亡θγταREEsIDE，1932， as is demonstrated by the close resem－ blance in the immature stage． The subgenus 1吻γα仇o加α， established above， is especially allied to Yαbθ乞6θγα8， because it has 」F▼oグγθ8εθ冗α （1戸0γγθ8¢θ7・Zα） like inner whorls but tends to lose the ornament on the outer whorl． yαbθ乞cθγα8 is， however， much more evolute and more widely umbilicate than 1吻γα伽o£oα． The inner whorls of the latter are compressed， instead of depressed， and have a fastigate， instead of rounded， venter with more distinct ventrolateral and ventral tubercles． The suture of the type－species of yαbθτ6θγじα8， Y． oγ‘θ7z£α1θ， has a nar－

rower1 丘rst lateral lobe than that of 1レf脚α仇o¢oα，1レf．〃θzoθη8ゼ8． In the evolute shell， smoothed outer whorl and other respects Yαbθi¢θγα8 is apparently similar to 18励αγτ¢θγα8 MATsuMoTo，1965． With respect to the 324 T．MATSUMOTO shell－form， omamentation and sutures of the inner whorls 18ん沈αγτoθγα8 is closely allied to O的θIZαWIEDMANN，1959， a subgenus of G励ん乞θ惚θγα8 DE GRossouvRE，1894，0f the Peroniceratinae， and is unrelated with Foγγθ8毒eγiαof the Barroissiceratinae． This is an example of synchronous homoeomorphy be－ tween the two subfamilies． 1万8加i6μ翻o％．－The hitherto described species occur in the Coniacian of Japan and Madagascar． In view of the long distance between the七wo regions and also of the world－wide distribution of the Barroisiceratinae， more examples of yαbθ‘6θγα8 could be expected to occur in other regions．

yαbθ‘6θγα80γゼθ励α1θToKuNAGA and SHIMIzu，1926 P1．44［32］， Figs．1－2；Pl．45 ［33］， Fig．1；Text－figs．12－13

1926． γαbθτ6θγα80冗θ川αZθToKuNAGA and SHIMIzu， Jo祝γ． Fαc． S6i．，1仇P． L7％初． 欠o〃〃o，sect．2， vo1．1， pt．6， p．201， p1．22， fig．7；pl．27，6g．1． 1926． γαbθτ6θγα80γτθ励α1θ，SHIMIzu， Pγoo．1仇P． Acαd．」αPαη， vo1．2， no．10， p．547． 1964． yα6θτcθγα8 0γiθ励αZθ， ］MATsuMoTo， OBATA， MAEDA and SATo， Trαη8． PαZαθo励．So6．」αραη， N． S．， No．56， p．323， p1．48， figs．1－2；text－figs．1－3．

T〃Pθ．－The holotype， described and figured by ToKuNAGA and SHIMIzu （1926，indicated above）， was almost certainly destroyed by fire in 1944． It came from the Iower part of Futa．be Group， Fukushima Prefecture． GK且5556， aspecimen from the same Iocality and described by MATsuMoTo et al．（1964， P．323，pl．48，五9．2；text－69．2） should be ofncially proposed as the neotype and

Qー 3

ノ／ノ’ 、＼1 C3

／ ／L斥1ー 、

＼ ろ∫ こ㎡． N ” 02

、 （， プ ＞ C2 1，， 」， ’1 k

q 20mm b 」＿r－＿＿＿」 Cl

Fig．12． Yαbθτ¢θ㌍α80ηθ励αZθToKuNAGA and SHIMIzu．

GK． H5624， from Ikushumbets． Diagrammatic sketches of lateral（a）and ventra1（b）views and also whorl－sections（C1， C2， and C3）at Q1， Q2 and Q3． （T．M． dθ屍？z．） AMonograph of the Collignolliceratidae from Hokkaido． Part III 325

b 10mm 1

し

U3

」口＿一」 C

Fig．13． Yαbθi6θγα80γiθ励α‘θToKuNAGA and SHIMIzu．

IGPS．35342， from Bibai． Whorl－sections（a， b）and an external suture（c）． （T．M． dθ1τγτ．） its validity should be acknowledged． Mα¢♂αL－Two specimens from Hokkaido， GK． H5624， from Ikushumbe七s （Mikasa High School Collection）， and IGPS．35342， from Bibai（original material of SHIMIzU，1926）． The specimens from Futaba are also taken into consideration． Spθc萌c¢んαγα¢τθγ8．－The shell is moderately large， about 150 to 170 mm in diameter at the full grown－stage． It is evolute， about a quarter to one七hird of the inner whorl being embraced by the outer， although the immature shell may be less so． The umbilicus is wide in the middle to late growth－stages， ranging from 40 to 48 percent of the entire shell diameter． The inner whorls are more or less depressed， broadest in the lower par七 and subrounded in cross－section， having inflated flanks， subrounded umbilical shoulders， rounded， gently sloping ventrolateral shoulders and a more or less broadly arched， weakly keeled venter． They are ornamented with considerably large， strong， mediolateral tubercles and thick ribs which extend from七he umbilical margin to the Iateral tubercles． On the ven七rolateral part， which is overlapped by the outer whorl， there are in the earlier stages ventrolateral tubercles resting on weak scondary ribs which are bifurcated and projected from the Iateral tubercles． They disappear at about the shell diameter of about 600r 70 mm．， when the faint extensions of the major ribs and the lirae are projected from七he still strong lateral tubercles． Then， sooner or later， the lateral tubercles and the major ribs are weakened． At this stage the ventral keel remains， as a blunt eleva七ion． 326 T．］MATSUMOTO

In the adult stage， at about the shell diameter of 800r 90 mm．， there is a remarkable change in the shell－form and the ornament． The outer whorl， over that diameter， is higher than broad， having only gently convex， flattened， some－ what convergent flanks， low vertical or rather overhanging umbilical wall， abruptly rounded or rather subangular umbilical shoulder， indistinct， rounded ventrolateral shoulders and a gently arched or rather flattened venter． The faint keel is discernible on the earlier part of this stage but is sooner or later lost on the later part． The whorl is entirely smooth， without costae and tubercles． The lirae which may be discernible on the surface of the test are concave on the flank and gradually projected on the venter． The body－whorl is very long， occupying about an entire outer whorl or more． The suture consists of E， L， U2， U3（＝S）， U1， and I． In the Iate growth－ stage the elements are moderately deeply incised；Lis as deep as or slightly deeper than E， Ionger than broad and rather irregularly subdivided；U2 is much smaller than L；the五rst lateral saddle（between E and L）is narrowed at the stem and moderately deeply divided on the head；the second Iateral saddle（be－ tween L and U2），situated on the row of Iateral tubercles， is rather massive， having abroad base．

2レfθα82zγθγηθ？z£8．＿

Specimen［Part］ Diameter Umbilicus Height Breadth B．／H． IGPS．35342 163．0（1） 68．0（．42） 54．0（．33） 40．0（．25） 0．74 〃 Ll vol．］ 82．0（1） 27．1（．33） 32．3（．39） 31．9（．39） 0．99（ic） 〃L3／2 vol．］ 23．0 23．5 1．02（ic） 〃 ［〃 〃］ 55．3（1） 16．8（．30） 21．2（．38） 28．6（．51） 1．34（c）

GK． H5624 80．0（1） 35．5（．44） 24．0（．30） 25．2（．31） 1．05（ic） 〃 ［＿1／4vol．］ 67．5（1） 29．5（．43） 23．0（．34） 29．0（．43） 1．26（ic） 〃 ［〃 〃］ 23．0（．34） 32．0（．47） 1．39（c）

且olotype 62．0（1） 26．0（．41） 22．0（．35） 26．0（．42） 1．18（ic）

GK． H5556 123．0（1） 59．4（．48） 39．6（．32） 31．6（．25） 0．8

Rθ勿α励8．－One of the specimens from Hokkaido， GK． H5624， is very similar to the holotype from Futaba． Ano七her example， IGPS．35342， is less widely um－ bilicate than the holotype at the corresponding stage（with the diameter of about 80 mm．）and also somewha七less widely umbilicate than a similarly Iarge example from Futaba（i．e． GK． H5556 described by MATsuMoTo et al．，1964） a七the full－grown stage． These and other minor differences are regarded as variations in one and the same species． IGPS．35342 is probably the specimen on which SHIMIzu（1926， p．547）gave a remark． Co仇Pαγ乞80η．－yα6θ60θ夕α80γZθ励α1θmost typically represents the generaI character of the genus yαbθi6θγα3． It is so to speak on the average of the variability of yαbθZoθγα8， from such a depressed and coarsely tuberclate species asγ．勿θηαbθη8θto such a less inHa七ed and predominantly costate species as γ．α批伽α勧θη8θ． As Co肌IGNoN（1965， P．82）noticed， yαbθZ6θγα8抗劫bθγ6％1α£z棚CoLLIGNoN from Madagascar closely resemblesγ． oγ乞θ励αZ¢from Japan． The distinction AMonograph of the Collignoniceratidae from Hokkaido． Part III 327 is a smaller number of coarser Iateral tubercles in the Madagascar species． More than 12 tubercles（or major ribs）are counted per whorl in the middle growth－stage（i．e． immediately preceding to七he smooth last whorl＞of Y． oがθ励α1θ，whereas about 90r so in that of y． bZ枷bθγの∂α飢仇． This difference is by no means great and the resemblance in other respects is so close that the subspecific separation could possibly be considered． This should be examined by comparing Populations in the two regions． Oco蹴γθηcθ．－GI（． H5624 came from the zone of 1％ocθγα仇μsμωαブ物θη8Z8， in the Kamisama七a－zawa， a tributary of the upper reaches of the Ikushumbets （17km point along the abandoned forestry railway）；IGPS．35342 was found in a calcareous nodule of dark green fine－sandy siltstone， as a pebble in the Bibai－gawa， east of Bibai coal－mine， together with抗06θγα祝μ8 cf．μωαグ伽凱8乞s； both in the province of Ishikari， central Hokkaido． The holotype and the hypotypes of MATsUMoTO et al．（1964）were found in nodular calcareous sandstone in the Lower Conglomerate Member of七he Futaba Formation， in the upper reaches of the Sakura－zawa， Oriki， Futaba－gun， Fukushima Prefecture， i．e． the Pacific coast of Northeast Japan．1π06θγα働μ8 祝ωα元ぜ糀梛8Z80ccurs abundantly in the same member． To sum up YαbθZ6θγα80γZθηεα1θoccurs in the zone of 1η06θγα仇μ8μωα元伽θη一 8乞8，i．e． the main part of the Lower Urakawa， Coniacian．

Genus 17αγZeπθ8 REEsIDE，1932

T〃pθ一8pθcτθ8．－BαηoZ8τ6θγαs（Hα弼θπθs）んαγ1θZ DE GRossouvRE，1894（origi－ nal designation）． GθηθγZc碗αgη08乞8．－The shell is rather small， much involute and compressed． The umbilicus is narrow and surrounded by low but steep umbilical wall． The whorl is much higher than broad， having Hattened flanks and a narrow， fastigate venter with a sharp keel persisting throughout growth． The shell is ornamented with weak， fine， more or less flexuous ribs， with bifurcated or inserted secondaries on the outer part of the flank． They tend to disappear in the last growth－s七age． The umbilical tubercles at the end of the primary ribs may be distinct or indistinct（or almost undeveloped）． Weak mediolateral tubercles may be discernible on the inner whorls and disappear on the outer whorl in some species， but may not be perceptible in other species． The ventrolateral and ventral clavi are numerous and comparatively distinct， persisting to the last stage． The suture is of rather reduced type， consisting of massive saddle and less deeply incised lobes． The auxiliary elements may be apparently numerous owing to subdivision． 1～θ勿α袖8．－The following species are examples which are referable to

11α7・1θ祝θ8：

月「．〃αγZετ（DE GRossouvRE，1894） 1了．αls¢α（1θ？zθη8Z8 （ScHI・UTER，1876） 17．cα8εθIIθγτ8i8 （REESIDE，1932） 328 T．］MATSUMOTO

1了．bγ庇ggθ励（BASSE，1947） 17．b〃zα6θητ¢％8 （PERvINQuI島RE，1907） H．初αηαsoαθη8Z8（BASSE，1947） 17．6θη加冗PARNEs，1964 These species occur in the Coniacian strata． An example from且okkaido， described below， is comparable to the丘rst species， although it is incompletely preserved． Oo仇pαγ680ηα閲α扱励句．－HαゲZθ勧θ8 was established by FEEslDE（1932， p．14） as a subgenus of Bαγγoi8Z6θγα8． REYMENT （1954， P．268；1955， P．67） and WRIGHT（1957， p． L434）treated it as a subgenus of 170惚8τθ働and regarded Als亡α∂θ働毒θs REEslDE，1932 ［type－species Ammo物社θs αlsfα（1θηθη8乞8 ScHL6TER， 1876］as its synonym． PARNEs（1964， p．21）treated it as a dis七inc七genus， be－ cause he took little account of the mediolateral tubercles． Iwould not disregard the mediolateral tubercles in spite of their apparent variability． This and other characters suggest that Hαγ1θ党θs is closely related to the compressed subgroup of、Foγγθ8ZθγZα． However， the ornaments on the flank are so weakened in正rαグZθ屹8 that the mediolateral tubercles remain only on the inner whorls of certain species． Apart from this character，∬αγZθπθ8 can be distinguished from Foγγθs£θγiαin several other points． Namely i七has much more illvolute shell， a narrower umbilicus， more compressed whorls， 且attened Hanks， a narrower venter，6ner and weaker lateral ornaments， finer， more numerous and more persistent ventrolateral and ventral tubercles， and more reduced suture．lilles． HαγZθ批8is similar to 801gθγ飽8 in the compressed shell and the weakened ornament， but the fastigate venter with numerous ventrolateral and ventral clavi ls more persistent in Hαγ1θ批8．

11αγ1θ乞舌θ8sp． cf．1f．んαγZθ乞（DE GRossouvRE） P1．43［31］， Fig．2；Text－fig．14

ComPαγe．一 1894． Bαγγoづ8τcθγα8んαbθηθZ抗θγ乞var．んαパθZ I）E GRossouvRE， M6祝．1伽μ．0αγ¢θ G〈多oム刀6¢．Fγαγz（ハθ，1893， p．56， pl．2， figs．2，7，8． 1894． Bα㌍ゲoτ8τ6θγα8んα6θげθZZ↑τθγ‘var．αZ8Zα（Zθηθη8Z8， DE GRossOuvRE （πo舵ScH－ LUTER，1876），1M（》．， p．55， p1．2，6g．4． 1904． Bαγγoi8icθγα8 んαbθγプθIIηe効 var． んαγ・Zθi， SOLGER， Bθiぴ． Gθol． Kα？ηθγμη， p．172，figs．58－61． 1932． Bα宵oi8τ6θγα8（1irαγzθ泣θ8）ん翻eτ， REESIDE，び． S．σθo乙Sμγ勿． Pγo∫． PαPθ㌍， 170－B，p．14． 1947． 170γ㌍θ8彦θηα （1irαγzθτ¢θ8）んαwZθi， BAssE，ノ1ηη． Pα160励． vo1．33， P．139 ［43］．

』ZατθγZαZ．－IGPS．54745， a single， imperfectly preserved specimen from Gono－ sawa， Pombets． Dθ86γ⑳励θγθ仇α励8．－The specimen shows the shell－form of Hαγ1θ屹8 玩γZθZin its involute， fairly rapidly growing shell， consisting of compressed， high whorls with Hattened， convergent flanks， subangular umbilical shoulders and a fastigate， narrow venter． It is not so compressed as the holotype（DE AMonograph of the Collignoniceratidae from Hokkaido， Part III 329

ε し （ぷO u2

03《・5｝

l l P〜’θーノ 「1，ノ 1‘‘‘i 、し、 、 ノ V－1、

‘ q b 》 5mm 10rnπ、 － 、ノ Fig．14． Hαγ1θπθ8 sp． cf．1r．みα㌍／θi（DE GRossouvRE）．

IGPS．54745， from Gono－sawa［＝Takino－sawa］， Pombets． External suture．s （a）at d＝30 mm． and whorl section（b）． （T．M． dθZiη．）

GRossouvRE，1894， pl．2， fig．2）of Hαγ1雄θsんαγZθi， but is similar七〇七he less compressed variety of H．〃αγ1θτ， exemplified by the specimen of DE GRossouvRE’s （1894） pl．2， ng．4． The observable ornament is also within the variation of H．んαγ1θZ， being similar to that of DE GRo．ssouvRE’s（1894， pl．2，6g．7）‘‘intermediate variety between var．α18fα∂θηθη8Z8 and var．んαγ1θ乞，”but the mediolateral tubercles in the Hokkaido specimen are weaker than those of七hat specimen． The ven七rolateral and ventral clavi are as distinct as in that French specimen． DE GRossouvRE （1894）did not illustrate the suture of H．1LαγZθ‘itself． The Iast suture of the Hokkaido 8pecimen shows rather massive lateral saddles， amoderately broad lateral lobes（L and U2）and apparently numerous， descend－ ing auxiliaries． In the general aspects it is similar to， if not identical with， the illustrated suture of力「αγ1θ儲θ8 cα8亡θIIθγ↓8Zs （REEsIDE） （1932， pl．6， fig．5）．

1レτθα8％γθ？7τθγ↓¢S．－

Diameter UmbiliCUS Height Breadth B．／且． IGPS．54745 35．5（1） 6．3（．18） 19．8（．56） 13．1（．37） 0．66

Occ祝γγθη¢θ．－Gono－sawa ［＝‘‘Takinosawa”］， Pombets， a tributary of the Ikushumbets， central Hokkaido， zone of 1η06θ筏働鵬μωα∬物θη8Z8． The specimen is coated by dark green matter as in other specimens of the same stream．

References Cited

The references cited in Part III are mostly listed in the bibliography in Part I． They are not repeated here． The following is a supplementary list of references which should be added to the l）ibliography． Two misprinted references in Part I are also included in the list， with amendment．

CoBBAN， W． A．（1953）：Cenomanian ammoni七e fauna from the Mosby Sandstone of central Montana． σ． S． GθoZ． S微砂． Pγoグ． Pαpθγ243－D，45－55， pls．1－12． CoLLIGNoN， Maurice （1965）： ∠4亡1αs （1θ8 Fo88ilθ8 Cαγα¢εθη8がqτ↓θ8 ∂θ 1匪αdαgαs6αγ （ノ1γη？η07膓元¢θ8），13（Coniacien），1－88， pls．414－454， Serv． G601．， Tananarive． CoQuAND，］M． H．（1859）： Synopsis des animaux et des v696taux fossils observ6s dans 330 T．MATSUMOTO

1a formation cr6tac6e du sud－ouest de la France． BμZZ． So6． G601．17γ伽6θ，［2］， 16，945－1023． HoEPEN， E． C． N． vAN（1957）： The deposits on the Umsinene River． C． R．， CC2▼∠4， Gθo乙ταηαηαγ初θ，Serv． G601．］Madagascar，2，349－350． （1968）： New and little known Zululand and Pondoland ammonites．∠4ηη． Gθol． Sμγrり．S．∠1∫γ．，4 （1965），157－181， inc1． pls．1－10． LlssoN， C．1．（1908）： Coη加訪μガ6ηαZ coγ乙ocτ働τθ？τ¢080bγθαZgM↓08αγηηzoγτπθ8 dθZ Pθγ庇． 66p．，23 pls．， Lima［4°Congreso Cient． Latino・・Americano，1°Pan－Americano， celebr． en Santiago de Chile］． LoMBARD， J．（1930）： C6phalopodes et Lamellibranches cr6tac6s du Congo frangais． BμZL Soo． G60Z． Fγαγτcθ， ［4］，30，277－322， pls．29－33． LUTHY， Jacob（1918）： Beitrag zur Geologie und Palaentologie von Peru． M6M． Soc． PαZ607乙£． Sμτ8sθ，43，（5），1－87， pls．1－5． MATsuMoTo， Tatsuro（1965）：Amonograph of the Collignolniceratidae from Hokkaido． Part I and Part II． ルτθ批． Fαc． S6τ．， K〃zL8んμση初．，［D］， Geol．，16，（1），1－80， pls．1－18［Part I］；（3），209－243， pls．36－43［Part II］． MATsuMoTo， Tatsuro・， OBATA， Ikuwo， MAEDA， Shiro， and SATo， Teruo（1964）： γαbθZ－ cθγα8（Cretaceous ammonites）from Futal）a， northeast Japan． 野αη8． Pγ06． Pα1αθo励．S促．」αpαπ，［N． S．］，（56），322－331， p1．48． PARNEs， A．（1964）： Coniacian ammonites from the Negev（southern Israel）．み砿L Gθol． Sz‘γ〃．18γαθZ， （39），1－42， pls．1－4． REEsIDE， J． B． Jr．（1932）： The Upper Cretaceous ammonite genus Bα”o緬oθγα8 in the United States． σ． S． Gθo乙S祝γu．， Pγo∫． Pαpθγ170・B （for 1931），9－29， pls．3－10． SPATH，1．． F．（1931）： Amonograph of the Ammonoidea of the Gault． Part 8． Pα1αθ一 〇？τZo9γ． So6．，1929，1」ondon，313－378， pls．31－36． STEINMANN， G．（1930）： Gθologτθ砂oηPθγ庇，448 pp．，9pls．，1map， Heidelberg． VENzo， Sergio（1936）： Cefalopodi del Cretaceo mediosuperiore dello Zululand． PαZ． 1εαZτ6α，36，59－133，pls．5－12． Tatsuro MATSUMOTO

AMonograph of the Collignoniceratidae from Hokkaido

Part III

Plates 39［27］～45［33］

1（yushu University（1． HAYAMI）photos， without whitening， unless otherwise stated． Plate 39 Explanation of Plate 39［27］

Fig．1． Bαγγθi8icθγαs （Eα88のcθγαs）Mo7っzα抗m sp． nov．．．．．．．．．．．．．Page 303 Holotype， GK． H5460［＝MuRAMoTo Co11． P5－6234］，from Gono－sawa， Pombets， zone of 1ηocθγα脱視8れ〃α元τ阻eηsτ8， Upper Yezo Group， Ikushumbets area， Ishi－ kari Province， central Hokkaido． Two latera1（a， b），ventral（c）and aper－ tural views of an adult specimen， in natural size（×1）． Mem． Fac． Sci．， Kyushu Univ．， Ser． D， VoL XIX Plate 39

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1c

∨’ヤキ s

T，MATSUMOTO： Collignoniceratidae［Pl．27］ Plate 40 Explanation of Plate 40［28］

Figs．1－4． Foγγθ8εθτ・τα（F「oγγ・θ8τθ万α）α〃z｛αz‘（冠i（BouLE， LEMoINE and TIIEvENIN）・・．・・．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．Page 308 1．GK H5622， from loc． Ik 2119p， Gono－sawa， Pombets（H． KoKuBu Coll．）． Two latera1（a， b），apertural（c）and ventral（d）views of a shell of the middle growth－stage，×1． 2．GK． H5623， from loc． Ik 2147p， Gono－sawa， Pombets（T． TAKAHAsHI Coll．）． Two latera1（a， b），ventral（c）and apertural（d）views of an immature shell， ×1．5． 3．GK． H5464［＝T． MuRAMoTo Coll． P5－2451］， from Gono－sawa， Pombets． Lateral view of another immature specimen，×1．5． 4．GI（． H5442 ［＝T． MuRAMoTo Coll．2156］， from Ik 2156， Gono－sawa， Pombets． 1、ateral（a）and ventral（b）views of a specimen of a late growth・stage，×1． All the figured specimens came from the zone of 1ηooθ7w肌8μωαガれθηsis， Upper Yezo Group， Ikushumbets area， Ishikari Province， central Hokkaido． Mem． Fac． Sci．， Kyushu Univ．， Ser． D， Vol． XIX Plate 40

2c

1a 1c

警 2a

1b 1d

2b

罐

2d

T・］M【ATSuMOTO： Collignoniceratidae1［Pl・28］ Plate 41 Explanation of Plate 41［29］

Fig．1． 1汀o宵θ8εθγづα （1Poγγθ8古θがα）αγ批αZαsp． nov．．．．．．．．，．．．．．．．．．Page 313 Holotype， GK． H5621， from loc． Ik 2144p， Gono－sawa， Pombets， zone of 1ηooθγα彿τ‘8祝ωαゴτ働例8Z8， Upper Yezo Group， Ikushumbets area， Ishikari Province， Hokkaido （Coll． T． TAKAHAsHI）． La七eral（a）and two ventral （b，c）views of an adult she11，×1． Mem・Fac． Sci．， Kyushu Univ．， Ser． D， Vol． XIX Plate 41

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∂叉d

1b

T．MATsuMoTo：Collignoniceratidae［Pl．29］ Plate 42 Explanation of Plate 42［30］

Figs． 1－2． Foγγ・¢8εθηα （～∬zω・αγ〃o亡oα）〃θzo杉γzsZ8 sp． nov．．．．．．．．．．．．．．Page 317 1． Paratype， GK． H5463， from Gono－sawa， Pombets， zone of 1ηocθγαηzμs μ初αガ侃θη8τ8，Upper Yezo Group， Ikushumbets area， Ishikari Province， central Hokkaido（Co11． T． MuRAMoTo）． Two lateral（a， b）and ventraI （c）views of an immature specimen， enlarged，×2．2． 2． Holotype， GK． H5462， from Ioc． Ik 2155 p1， Gono－sawa， Pombets， zone of 1ηo¢θγα微偲祝初α」伽θη8τ8，Upper Yezo Group， Ikushumbets area， Ishikari Province， central Hokkaido （Co11． T．］MuRAMoTo）． Two latera1（a， b）， ventra1（c）and apertura1（d）views of an adult shel1，×1． Mem． Fac． Sci．，1（yushu Univ．， Ser． D， Vol． XIX Plate 42

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a

→ 、煕 c烏村一・癒

T・］M【ATsuMOTO： Collignoniceratidae［P1．30］ Plate 43 Explanation of Plate 43［31］

Fig．1． Foγγθ8εθγτα （Mzτγα7πofoα） γημγαmo¢oi sp． nov．．．．．．．．．．．．．．．Page 320 Holotype， GK． H5620， from loc． Ik 2150p， Gono－sawa， Pombets， zone of 1ηocθγα仇視8脇〃α元批θη8τ8， Upper Yezo Group， Ikushumbets area， Ishikari Province， central Hokkaido （T． MuRAMoTo Coll．）． Two latera1（a， b）， apertural（c）and ventral（d）views of a probably adult shel1，×1． Fig．2． 1ゴαγZθほθ8 sp． cf． H．んαγ1θτ（DE GRossouvRE） ．．．．．．．．．．．．．．．．Page 328 1GPS．54745， from‘‘Takino－sawa，，［＝Gono－sawa］， Pombets， a tributary of the Ikushumbets， Ishikari Province， central Hokkaido（Tohoku Univ． Coll．）． Two latera1（a， b）and ventra1（c）（upside down）views of a defective speci－ men，×1．5．（Tohoku University photos．） Mem． Fac． Sci．， Kyushu Univ．， Ser． D， Vo1． XIX Plate 43

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T，MATSuMOTo： Collignoniceratidae［Pl．31］ Plate 44 Explanation of Plate 44［32］

FigS． 1－2． γαbθτcθγα80γτθγz¢αZθToKuNAGA and SHIMIzu．．．．．．．．．．．．Page 324 1． GK． H5624， from Kamisamata－zawa， a tributary of the upper reaches of the Ikushumbets， near the 17 km． point， zone olf 1ηo¢θγαMz↓sμωα元τ働θη8τs， Upper Yezo Group， Ikushumbets area， Ishikari Province， central Hokkaido （collected by NAITo， a student of Mikasa High Schoo、1）． Lateral（a）and ventra1（b）views， of a probably adult， but small， specimen，×1． 2． IGPS．35342， from a pebble in the Bibai， about 8 km． north of Ikushumbets， Ishikari Province， central Hokkaido（Toho‘ku University Coll．）． Lateral view of an adult specimen，×0．9． See P1．45［33］for other views．（Tohoku University photos．） Mem． Fac， Sci．，1（yushu Univ．， Ser． D， Vol． XIX Plate 44

T，MATSUMoTo：Collignoniceratidae［Pl．32］ Plate 45 Explanation of Plate 45 ［33］

Fig．1． γαbθτ¢杉γα80γτθγz¢α．1θToKuNAGA and SHIMIzu．．．．．．．．．．．．．．．Page 324 1GPS．35342， from a pel）ble in the Bibai， abo・ut 8 km． north of Ikushumbets， Ishikari Province， central Hokkaido（Tohoku University Collection）． Lateral （a），ventral（1））and apertura1（c）views of an adult specimen，×0．9． See P1．44［32］，Fig．2for another view．（Tohoku University photos．） Mem． Fac． Sci．， Kyushu Univ．， Ser． D， Vol． XIX Plate 45

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＼、

T．MATsuMoTo： Collignoniceratldae［Pl．33］