鹭。tage。。，，。。。ev。nia。。ystemby W. Ziegler and G．Klapper

The Subcommission on Devonian Stratigraphy has

formally agreed upon the nomenclature for seven

Standard Stages of the Devonian System. A basal

boundary stratotype is described in this article forthe Eifelian Stage, coincident with the base of the

Middle Devonian Series. Criteria for recognizing a

Givetian-Frasnian Stage boundary（＝base of UpperDevonian Series) and a Frasnian-Famennian Stage

boundary are also outlined． Future work will com-

plete the definition of basal boundary stratotypesfor each Stage.

MO

Introduction

Annual meetings of the Subcommission on Devonian Stra-tigraphy (SDS) have been held since its foundation in 1973,with important decisions summarized here on stratigraphicstandards being made in 1979, 1981, 1982 and 1983; thesehave now been formally ratified by lUGS. Each of thesemeetings, associated with field excursions to the Devonian ofmany countries, stimulated a wealth of Devonian researchthroughout the world. An earlier account in Episodes (Zieglerand Klapper, 1982) summarized the SDS decisions then taken;certain diagrams in that paper are repeated here so as tomake this account self-contained.

Devonian Stage Names

The agreed Stage names of the Devonian System (seeaccompanying article by Bassett) are as follows:

Upper Devonian 一 Famennian 一 Frasnian

Middle Devonian 一 Givetian 一 Eifelian

Lower Devonian 一 Emsian

一 Pragian 一 Lochkovian

厂厂帐二丈

吓七刃

With the exception of the lower limit of the LochkovianStage, which coincides with the lower boundary of theDevonian System (McLaren, 1973), all the Lower Devonianstages still await new boundary definitions. The decision onthe nomenclature of the Devonian stages also contains thestatement that the classic areas of the Lower Devonian in

the Ardenno-Rhenish Region (Belgium一West Germany) areno longer acceptable as satisfactory for Lower Devonianstage boundaries. Decisions on the lower levels of thePragian and Emsian stages will be based on different regionsin the next few years.

The decision on the Lower-Middle Devonian Series boundary(see below) also emphasizes the fact that Eifelian is the nameof the first Middle Devonian stage. The lower level of theGivetian Stage needs further studies prior to its formaldefinition.

W P173

120}

一一奋嚓票} - p"1-

W P 1

Figure 1： Locality maps of the site of the

boundary stratotype of the pa些些U三-boundary at theWetteldarf Richtschnitt, Eifel Hills, F.R.G. Bottomsection shows site of old trenches （＝ solid black

line) and 1982 trench （＝ parallel line with hatches

at both ends)； WP 1-173 ＝ measured units; dashed

oblique line between patulus Zone and partitus Zone＝Lower-Middle Devonian Series Boundary. H. -Fm. ＝

Heisdorf Formation, W.-Fm.＝Wetteldarf Formation.

〕 50 10O }． · ， r 一 。 I

104 Episodes, Vol. 8, No. 2, June 1985

．

。︸0︸‘‘刃．Q

O

击三o’u臼‘0二的n了UD乞

沪n。U气曰1﹄搜rsi了U－一

叻刁细‘0，﹂一﹄艺江

The lower limit of the Upper Devonian Series coincides withthe lower limit of the Frasnian Stage; the definition ofchronostratigraphic level is discussed in the following. Thelower limit of the second Upper Devonian Stage, theFamennian Stage is also newly defined.

LOWER-MIDDLE DEVONIAN SERIES BOUNDARY

Definition

黔 曰 O e 拭

t } M . . . 1, t} , - d- t, sel}ted gc n旧fit.}

厂一一一－ ｝— 11 ｝

生了湘，沪‘eel︾。匕ld

的n～Lrsi口‘。

于峨

囚2

0卜叭囚乏

二

D︸D︺1”“

目山卜OH目

山工1﹂0

山的哎山

比，一D︸a‘仍‘︸乳石

曰n～－‘︺‘1‘叭

击1一﹄Du。只争

51一浇

的，叶。中1。﹄J︸叫明川护UD工－︺仍

的n︸。UD工舒DU戏

．．

‘，．

．

一

团二‘

1们的1户0︸

u哑

夏：｛‘刻

0五r

6盯。〔e「。一仲5 0「0‘

门川曰川岁阔圈～层四国柑目﹃注民

曰．

叭1目1－今uesoUu

‘份曰

ul‘户识

c仁

～‘u

为箱州曰

一川引，引酬詹扛乳

注n曰屯们，司川户0峋江

以，户。︸们0．几

一

奉1

今触曰刽动川升到引引弓十

一

少‘品邵引州引

u创里田叹｜

甲

1

．

0︸0︸叨。叼1︺，oa

oul一01一全叻。︶口1，︸山。︺

的1价u‘己全oU

The boundary between the Lower and Middle Devonian Seriesis coincident with the lower boundary of the Eifelian Stage.The exact boundary level is chosen to coincide with the firstoccurrence of the conodont costatus partitusKlapper, Ziegler and Mashkova boundary).

m

︹艺

飞

︸日

r，es

esF

esesL

。乳扩

川

This stratigraphic level is the lower limit of the partituZone, a zonal subdivision of the conodont standard zonationthat was established during the 1970s (KIapper, 1971;Weddige and Ziegler, 1977; Weddige, 1977; Weddige et al.,1979; Klapper et al., 1978; Klapper and Ziegler, 1979).

Boundary Stratotype

The holostratotype of the巴些tus boundary is in the sectionexposed in the Wetteldorf Richtschnitt, near the town ofSchbneeken-Wetteldorf, Eifel Hills, Federal Republic of

Figuremiddle

3: Parastratotype columnar section of

Devonian Series Boundary, at Prastav

石ower-

quarry ,

near Prague, Czechoslovakia ． Numbered intervals arebeds。

70

Libra土

的工n口u己

－氏

1工ou之－二q的．三﹂0忿二口三－氏

明nu门ee﹂01口01闪已

的n︸1︸﹂门O

v比

的nlnl门d的n︸门1的ou的二二妇口u口全己

60

E上口二口

es47

Germany (Schdriecken mapsheet 1:25000, r 33 765 h 57 130;see Fig. 1). The Richtschnitt section is in a trench that wasfirst dug in 1937 (R. Richter, 1942; G. Solle, 1942) followingan international conference held in Diisseldorf on the Lower-

Middle Devonian Series boundary. The boundary between theHeisdorf Formation and the Lauch Formation, regarded asthe classic boundary between the Emsian and Eifelian oflong-standing German usage, was established in thisreference section.

For renewed discussions on the Emsian-Eifelian boundary, thetrench was reopened in the early 1970s, and to enable studyby the SDS it was widened and entrenched more deeply in1982 (Werner and Ziegler, in Ziegler and Werner, 1982; seeFig. 3 of Ziegler and Klapper, 1982).

The boundary section is exposed for a length of 45the strike of beds in the nearly N-S trench (Fig. 1),

church. The

in across

situated

area is

一

about 650 in SE of the Wetteldorf

pasture land that cannot be overbuiltby city expansion,34 the Senckenberg Research Institute

tfle trencn kaDou m 曰) ironiarea

iOr

and

of

60TTT

years. Theuncontrolled

whole area is fenced

has rented the

the communityoff in order to

山u0Z的n︸1︸﹄门d

access intermittent destruction

preventof the

EIIi section, and there is

The exposed beds are

andiUii access for scientific

part of the southern limbresearchers.

of the Prilin

尝 Horo. I 27

m2

1

0

︷1

｜｜土

土｜｜土

19

synclinal structure; the dip is to the NNW at 751.

A parastratotype section for the pa些itus boundary has alsobeen established. This is located at Prastav quarry, nearPrague, Czechoslovakia about 300 m east of the railwaystation Praha一Holyn6, and about 400 in north of the city busterminal "Holyn6l' (Chlup66,垫Ziegler and Werner, 1982).Lithostratigraphy of the Stratotype and Reference Sections

Holostratotype: The 1982 trench exposes, as did the earlierones, beds of the neritic Upper Heisdorf Formation and theLower Lauch Formation (lower part of Wolfenbach Member).

auo闪

的n－n和门d

It contains sample stations WP. I to WPtrench. The Lower-Middle

90 of

Series

Figure 2: Columnar section of basal Middle Devonianboundary stratotype, at the base of measured unit WP

30 in the Wetteldorf trench ． The section is composed

of limestones, bentonites (Harologium 1, 11, 111 andLibra I 一 xxx) and siltstones and marls (white

portions)．

(partitussection ( boundary) section lies see Figs. 1, 2).

Devonian

at 2 1.25 m of the

the 1971

boundary exposed

The Upper Heisdorf Formation comprises grey and greenmudstones and siltstones with little carbonate content and a

few argillaceous limestone beds or calcareous sandstones.Toward the top there is a distinct increase of regularlyinterbedded carbonate beds.

Episodes, Vol. 8, No. 2, June 1985 105

sticostatus group

partitus

patulusChotec

Trebotov

partitus boundary

Lauch

Heisdorf

buityncki

Figure 4 : Relationship of the Lower-MiddleDevonian Series Boundary (the paj生胜竺 boundary) tothe 砂yletic lineage from Polygnathus costatusPatulus to立 生 costatus, to the lineage from 立linquiformis bultyncki to the 立 robusticostatusgroup (sensu Weddige and Ziegler)， and to theHeisdorf-Lauch and Trebotov-Chotec- boundaries (from

Ziegler and Klapper,竺 Ziegler and Werner, 1982)·

correiating tne part坚us tiounciary

旦业咫些些竺 costatus pa些丝us is the second subspecies in adocumented conodont phyletic lineage (Fig. 4). The prede-cessor subSDecies is Polvgnathus costatus patulus KI.qnnpr-

1971 in the Lower Devonian, and the successor subspecies isPolvgnathus costatus costatus Klapper, 1971 in the Lower

Eifelian. Figures 3 and 4 illustrate the relationship of thepa些些s boundary to the phyletic lineage, the Heisdorf-Lauchand theChote6-Vebotov boundaries.

Polygnathus costatus巴rtitus is widespread geographically,occurring in Morocco, Spain, Germany, Carnic Alps, Czecho-slovakia, Central Asia, China, Malaysia, Australia, Nevada,Alaska, and the Canadian Arctic.

The conodonts of the parastratotype sequence in the Bar-r.qnriinn qrpn qrp ohnrpeteristiv, of the Polvgnathus biofacies

and thus contain a good reDresentation of the Polygnathus

costatus lineage. SDecies of Icriodus are rare, however. The

conodo-nts of the holostratotype sequence in the Eifel areaThe first

within a 5Polygnathuscostatus partitus occurs in also contains the Polygnathus costatus lineage, thus permit-eIn of fine-grained crinoidal ting intercorr elation of the two facies. The

nitic limestonethick layer，at 21.25 m above the base of the

WP. 30

calcare-

exposed sequence also has an abundant developmentsection, and just below the bentonite layer Horologium 11 (seeWerner and Winter, 1975, p. 344, and fig. 3). The base of the

Icriodus呼th Icriodus婴粤戮矛retrodepressusenTering iow in tne PUFLILUS Zone ivvUddl尽七,

holostratotypeof species ofBultynck, 1970in Ziegler and

partitus Zo竺is里 m b中w the少州orf-毕uc少吵undary.The base ot the hitellan Litage ana oitne mio。ie iievonianSeries is thus defined in the trench within the Upper HeisdorfFormation at a point 1.9 m below the base of the LowerLauch Formation.

The Lower Lauch Formation (Wolfenbach Member) ischaracterized by a sequence of alternating bluish-grey lime-stone and crinoidal limestone, green and grey mudstones andmarls, rarely with bluisb-grey calcareous sandstones. Beds ofmarl and mudstone increase in thickness toward the top.

The new trench in the Wetteldorf Richtschnitt contains the

following bentonite layers: Hercules I and 11 and HorologiumI一III of Heisdorfian age, and Libra I and II of Lauchian age(see Fig. 2).

Werner, 1982). The latter is an important and easily recog-nized subspecies that permits correlation with other neriticsequences in the Ardennes, Spain, England, and elsewhere(Fig. 5).

A major change in the megafauna (brachiopods, trilobites,goniatites) and in ostracodes and daeryoconarids occurs in alimited stratigraphic interval ranging from slightly below to

Parastratotype: The RE}!生竺 boundary is located herethe pelagic Vebotov Limestone. This is a light-grwell-bedded, mostly micritic and nodular limestone, with

hin

ey, an

increased amount of

(Chlup}6,垫Ziegler coarser organic detritusand Werner, 1982, p. 88).

in some beds

The boundaryfalls within 59-65 cm below the top of bed No. 9, and 2.8 mbelow the top of the Tfebotov Limestone, which is itselfoverlain by the Chote6 Limestone (Fig. 3).

Figure 5: World correlation chart of the par兰tusboundary in selected areas. occurrence of二.～ costatu三pa些些U三is marked by x. Note that precise conodontzone of the Edgecliff Member in the New York columnis unknown。 The Nedrow Member should be shown extend-

ing up into and the MOorehouse Member entirely withinthe costatus Zone. Information from: Carls et al．，1972; Klapper and Ziegler, 1979; Klapper et al．，1978; Weddige, 1977; Weddige and Zie卯er, 1977;Alberti，Chlupac, and Werner and Ziegler,竺 Zieglerand Werner, 1982; Bardashev and Ziegler, Bultynck,

Johnson et al．， Mawson et al．， Yolkin et al．， and

Ziegler and Wang,望 Ziegler, in press·

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坦一一。．﹄丁

106 Episodes, Vol. 8, No. 2, June 1985

slightly above the part丝jjs boundary. This faunal change isrecognizable from North Africa through Europe to CentralAsia and China, and analogues of this change are also recog-nizable in eastern North America (Werner and Ziegler,垫Ziegler and Werner, 1982).

Comment

In addition to the pa些j2s boundary, three other levels wereoriginally considered. The first was the lower boundary ofthe patulus Zone defined on the entry of旦costatus patulus.This level approximates to the base of the Couvinian Stage,long used for the base of the Middle Devonian of theArdennes.

A second candidate was the lower boundary of the坚些兰坐costatus Zone defined on the entry of立色costatus. Thiscoincides closely with the base of the Chote6 Limestone inthe Barrandian area. The third alternative was the lower

boundary of the旦eb些cens Zone defined on the entry of旦dehiscens Phillip and Jackson. This approximates to a level

T-the -base of the Favosites regularissimus Zone) used for manyyears as the base of the Middle Devonian in the Soviet Union.

Prior to the formation of the Subcommission in 1973, thequestion of the Lower-Middle Devonian boundary was seen ina new light by the publication of Carls and others (1972) inwhich a number of new and provocative correlations werepostulated.

Figure 7: SDS members examining Middle-UpperDevonian limestones on Bou Tschrafine Ridge, nearErford, Morocco. These and other Moroccan sections

have played a significant role in the clarification

of stratigraphical, palaeontological, facies, andpalaeogeographical problems of the Middle-UpperDevonian.

│C ... d"t zo-tio, A- ,oid F ..... │

│a名y而‘云护公... Z,,e│ Uppe, ZM' │｛ B}lgi.., W-G}- y │

│ │Middl. Z... │ │

│ │L.- Z- │ │

│ │L ...... }t Z... │ │

│di}Pa了峨瓦‘Z.- │up} │和刀ti- P- i │

│ │L" e │M - .., W-G.,...y │

│h- i} i- - Z... │Upp- S.1b- │- Itflobate Phmi- │

│ │ │M1- 10 │

│ │LO.- S,b- │ │

│- - Z- │Upp.r S.b- │ │

│ │Middl. Sub- │A� 记- 口 T1- (N,, Y,,k, Mo,mco)│

│ │ │},,i- - b- - │

│ │ │Wo- co, W-Ger- y) │

ot tne Lower旦sym里旦理里暨 conodont Zone, defined by thefirst occurrence of Ancyrodella rotundiloba (Bryant) andreferred to as the Lower asymmetricus Boundary. The Lowerasymmetricus Zone is a subdivision of the conodontzonation that was established in the early1962) and revised in the early 1970s (Ziegler,

Criteria for Correlation

1960s

1971).

standard

(Ziegler,

Ancyrodella rotundiloba. is an easily recognizable species thatis partof a well documented phylogeny.

species is Ancyrodella binodosa Uyeno 1967

Its predecessorand transitional

forms between A. binodosa and A. rotundiloba have been

illustrated by BuTtyr;C-1燕in(而acobs TI 9网下歹亘亚些些a wasthe rootstock of later species of Ancyrodella within theLower asymmetricus Zone:少 旦些望 Glenister and Klapper,1966; A.巡里班生望 Perri and Spalletta, 1981;色 塑gosaBranson and Mehl, 1934; and A. afr鱼cana Garcia-Lopez, 1981.All of these permit additional means of identification of theLower asymmetric些 Zone. A detailed description of theevolution of the early组些坚坐坐 species is given by Klapper(1985). A. rotundiloba is a wideSDread taxon ecologicallv.

occurring wiaeiy in Dotn neriTic anG peiagic iacies, ana Tne

species is well known from all relevant Devonian areas.

Figure 6: Diagram showing conodont zones andrelated positions of ammonoid faunas across the theMiddle-Upper Devonian Boundary. After Ziegler and

Klapper （纽 Ziegler and Werner, 1982)· The 生组～parilis Zone is divided informally into lower andupper parts.

The fact that there were four competing levels for the seriesboundary stimulated a great amount of research over a periodof eight years. This included especially research on cono-donts and conodont zonation (e.g. Weddige, 1977; Klapper etal., 1978), on dacryoconarids (e.g. Lotke, 1974, 1979; Lukeg,1977; Alberti,鱼 Ziegler and Werner, 1982), and goniatites

The following goniatite genera also have their first occur-rences within the Lower asvmmetricus Zone: Koenenites (in

tne kense usea oy ivi.tt. tiouse ana vv.-i-. Aircngasser),Probeloceras, and竿anticoceras.Comment

An historic level for the series boundary (and the lower limitof the Frasnian) coincides with the base of the Assise de

Frasnes in the Ardennes (Sartenaer,望Errera et al., 1972).This level is only slightly below the lower limit of the Lowerasymmetricus Zone.

Two other biostratigraphic levels were also consideredtime to time for the Middle-Upper Devonian seriesary. The first was marked by the entry of the里垫a

B

from

ound-

(e.g. ChlupA6 and Turek, 1983). After much discussion anddeliberation, the partitus boundary gained a clear majorityvote over the other levels.

MIDDLE-UPPER DEVONIAN SERIES BOUNDARY

Definition

The boundary between the Middle and Upper Devonian Seriesis coincident with the lower boundary of the Frasnian Stage.The exact level is chosen to coincide with the lower boundary

amplexum fauna, which coincides wiOzarkodina semialternqnq (Wirth) in th.

varcus Subzone. This biostratigraphic uppermost Middlelevel was strongly

而v石万ed by a few Devonian stratigraphers because of itscoincidence with one of the historic levels for the base of the

Upper Devonian (House,垫Ziegler and Werner, 1982).House argued that this coincides with the entry

Pharciceras amplexum7- x - I - } 华塑‘玉Fistone of New YorK, ano iur工h

（Fig. 6) withinthe Tullythat this fauna was

of the

Lime-

inter-

Episodes, Vol. 8, No. 2, June 1985 107

preted as part of the坦吧些些望 Zone, longregarded by ammonoid specialists as denotingthe base of the Upper Devonian. A counter-argument (Zeigler,坦 Ziegler and Werner,1982) is that the amplexum fauna is distinctlyolder, according to the conodont zonation,than the lunulicosta Zone in its original scope.

ThesiX,

latter has a stratigraphic rangeand possibly a

subzonal

ficientlydivisions

precise

seventh, conodontand therefore is

throughzonal or

not suf-

for definition of the

and Series boundary. Furthermore,ciceras is unknown in the Assise de

StagePhar-

三兮n只es a乎月，毕婴碑攀鹦乡冬now几尸nlyiorK ano morocco krigs.‘，ts ano w.

Frome-

in New

The second level considered was the lower

limit of the些 坐 Zone, defined on theentry of Palmatolepis disparilis Ziegler andMapper, 1976. The goniatite fauna charac-terized by the earliest occurrence of Pon-ticeras坠kayseri,旦pernai pernai,旦pernaiapplanata (see Ziegler and Mapper,垫Zieglerand Werner

Zone.1982) occurs within the disparilis

The first vote of SDS in 1981 was divided between the

disparilis and Lower asymmetricus boundaries, and effec-tively eliminated the Phar,ciceras amplexurn level fromfurther consideration. In the first vote in the 1982 meeting,five titular members voted for the旦些鲤些 Zone and fiveagainst. Subsequently seven titular members voted for, andthree against the base of the Lower asymmetricus Zone asthe biostratigraphic level for the base of the UpperDevonian. A final large majority vote was in favour of theLower asy里me丝icus Zone, and included the decision that thestratotype for the base of the Frasnian Stage and the UpperDevonian Series will be in pelagic facies. However, astratotype has not yet been selected and remains a matterfor future consideration.

Figure 8:1hrs, south

Middle-Upper Devonian sequence at Jebel

of Erford, Morocco。 Backpack for scale.

LOWER BOUNDARY OF THE FAMENNIAN STAGE

Definition

The exact level at which the basal boundary of this stage isto be defined is coincident with the lower limit of the Middle

Palmatolepis triangularis conodont Zone. This is defined bythe first occurrence of Palmatolepis delicatula Branson andMehl. This is a subdivision of the conodont standard zonation

that was established in the early 1960s (Ziegler, 1962).

Criteria for Correlation

Palmatolepis delicatula comprises two subspecies,旦 生

Fi gure 9: Examples of the rich Upper Devonian

ammonoid faunas known from Morocco. Abundant speci一mens such as these are commonly sold throughtoutMorocco to tourists.

delicatula and P.d. clarki, that evolved from the亘巫下To-ck. P.还巫鱼应巫一is widespread in pelagic

P. triangu-facies, and

in conodont terms in＿the＿ Palm醉olepisano 乙legler, itliv).

biofacies (Ziegler,1962, 1971; Klapper Correlation

near-shore facies is enabled by the first occurrence at

势is护vel of，粤垫竺iowaensis, which occurs in bothkoanuDerg ano Ureesen,1吕匕任).

with

about

facies

The1 lowere boundaryy of the。 Middle triangulariF Zone lieswithin close proximity to the historic base of the FamenniainStage (lower limit of the Schistes de Senzeilles, see e.g.,Bouckaert et al., 1972). The lowermost beds of the Schistesde Senzeilles in the type area are characterized by brachio-Pods, especiallv bv Pamoocilorhvnchus lecoMDtei and P. nux

E三旦旦卫圣WOUCKaeri et ai., iu-iz).

The lower boundary of the Famennian Stage is slightly belowthe first occurrence of the goniatite genus Che卫ocer些，which apparently first occurs near the base of the Upper

A boundary stratotype has not yet been selected for the baseof the Famennian Stage; it also remains a matter for futureconsideration.

Comment

The much-discussed Frasnian-Famennian biotic crisis duringwhich mass extinction in many invertebrate fossil groupsoccurred (McLaren, 1983) seems to have been restricted tothe UDDermost viffas Zone and Lower trianffularis Zone or

parts thereof (Ziegler, 1984). In many areas of neritic andpelagic facies during this interval, physical breaks in sedi-mentation or condensation are observed. Therefore, althoughthe lower limit of the Lower Palmatolepis trian吕 ularis Zoneis for palaeontological reasons an excellent contender for theFrasnian-Famennian Boundary, and possibly also in closeproximity with the traditional boundary, it is not regardednow as a desirable level at which to fix this boundary.

Palmatolepis triangularis Zone. Thethe goniatite genus Crickites is in

highest occurrence ofthe Lower triangularis

Zone below the proposed boundary level.

108 Episodes, Vol. 8, No. 2, June 1985

Prof. Dr. Willi Ziegler is Directorof the Senckenberg ResearchInstitute and Natural HistoryMuseum, D-6000 Frankfurt 1,F.R.G. and Professor of Palaeon-

tology and Geology at the Univer-sity of Marburg. He works mainlyon upper Palaeozoic stratigraphy,particularly Devonian conodontbiostratigraphy and palaeontology.As Secretary (1973-1976) andChairman (1976-1984) of the Sub-commission on Devonian Strati-

graphy, he has examined most

Korrelation mit

Jarhbuch

vol. 145,

fUr Ge

der Conodonten-Parachronologie. Neuesologie und Paldontologie Abhandlungen,

p. 183-206, pl. 1.

relevant sections of Devonian rocks throughout the world.Since 1984 he has been first Vice-Chairman of the Commis-

sion on Stratigraphy.

Dr. Gilbert Klapper is Professor ofGeology at the University of Iowa,Iowa City, Iowa 52242, U.S.A. Hisresearch concentrates on Silurian

and Devonian conodont taxonomyand biostratigraphy, with specialcurrent emphasis on the Frasniansequence in the Montagne Noire,France. He was Vice-Chairman of

the Devonian Subcommission from1976 to 1984.

Lotke, F.9 1979. Biostratigraphic significance of theDevonian Dacryoconarida. Palaeontological AssociationSpecial Paper, 23, p. 281-189.

Lukeg, P., 1977. Some index tentaculites (Nowakiidae) fromthe Lower/Middle Devonian boundary beds of the Barrandian.6asopis pro Mineralogii GeOlOgii, 22, no. 1, p. 19-28, p1s. 1-6.

McLaren, D.J., 1983. Bolides and biostratigraphy. Bulletin ofthe Geological Society of America, v. 94, p. 313-324.

Richter, R., 1942. Beitriige zum Richtschnitt Unterdevon/Mitteldevon bei Wetteldorf. Geschichte und Aufgabe desWetteldorfer Richtschnittes. Senckenbergiana Lethaea, Band25, p. 357-361.

Sandberg, C.A. and Dreesen, R., 1984. Late Devonianicriodontid biofacies models and alternate shallow-water

conodont zonation. Geological Society of America, SpecialPaper 196, p. 143-178.

Solle, G., 1942. Anlage und Aufnahme desRichtschnittes.

p. 361-389.Senckenbergiana Lethaea

Wetteldorfer

Band 25,

Weddige, K., 1977. Die Conodonten der Eifel-Stufe imTypusgebiet und in benachbarten Faziesgebieten. Sencken-bergiana Lethaea, 58, no. 415, p. 271-419.

Weddige, K. and Ziegler, W., 1977. Correlation of Lower/Middle Devonian boundary beds. Newsletters on Stratigraphy,vol. 6, p. 67-84.

Weddige, K., Werner, R. and Ziegler, W., 1979.

References

Bouckaert, J., Mouravieff, A., Streel, M., Thorez, J. andZiegler, W., 1972. The Frasnian-Famennian Boundary inBelgium. Geologica et Palaeontologica, 6, p. 87-92.

Bultynck P. and Jacobs, L., 1981. Conodontes et s6dimen-tologie des couches de passage du Givetien au Frasnien dansle nord du Tafilalt et dans le Ma'der (Maroc Pr6saharie动．

Bulletin Institut Royale Sciences Naturelles de Belgique,vol. 5 3, Sciences de la Terre, no. 2, 24p, pls. 10.

Carls, P., Gandl, J., Groos-Uffenorde, Helga, Jahnke, H. andWalliser, O.H., 1972. Neue Daten zur Grenze Unter-/Mittel-Devon. Newsletters on Stratigraphy, vol. 2, no. 3,p. 115-147.

Eifelian Boundary, an attemptEifel and Ardennes Regions.vol. 8,p. 159-169.

at correlation

Newsletters on

The Emsian-between the

Stratigraphy,

Werner, R.Grenzbereich

and Winter, J., 1975. Bentonit-Horizonte im

Richtschnitten.

p. 335-364.

Unterdevon/Mitteldevon in den EifelerSenckenbergiana Lethaea, Band 56, no. 4/5,

Ziegler, W., 1962. Taxionomie und Phylogenie Oberdevon-ischer Conodonten und ihre stratigraphische Bedeutung.Abhandlungen des Hessischen Landesamtes fUr Bodenfors-chung, Heft 38, p. 1-166, pls. 1-14.

Chlup96, 1. and Turek,the Barrandian area

V., 1983.，Devonian了 goni畔ites了毕rn U zecnosiovaKla. Ustreani U sL

Klapper, G., 1971. Sequence within the conodont genusPolygnathus in the New York lower Middle Devonian.Geologica et Pala eontologica, 5, p. 59-79, p1s. 1-3,

Klapper, G., 1985. Sequence in Conodont genus Ancyrodellin Lower asvmmetricus Zone (Earliest Frasnian, UpperDevonian) of the Montagne Noire, France. FaiaeonTograpnica

A, 188, p. 19-34.

Klapper, G. and Ziegler,W．，1979. Devonian conodont bio-stratigraphy. Palaeontological Association Special Paper 23,p. 199-224.

Klapper, G., Ziegler, W. and Mashkova, T.V., 1978. Cono-donts and correlation of Lower/ Middle-D evonian boundarybeds in the Barrandian area of Czechoslovakia. Geologica etPalaeontologica, 12, p. 103-115, pls. 1-2.

Lotke, F., 1974. Die Verbreitung von Tentaculiten (Dacryo-conarida) aus dem Unterdevon des SW-Harzes und ihre

Ziegler, W., 1971. Conodont stratigraphy of the EuropeanDevonian. Geological Society of America Memoir 127,p. 227-283.

Ziegler, W., 1984. Conodonts and the Frasnian-FramennianCrisis. Geological Society of America Abstract with Programs16, p. 73.

Ziegler, W. (ed.), in press. "on the Devonian." CourierForschungsinstitut Senckenberg 75.

Ziegler, W. and Klapper, G., 1982. Devonian Series Bound-aries: Decisions of the lUGS Subcommission. Episodesvol. 1982, no. 4, p. 18-21.

Ziegler, W. and Werner R. (eds.), 1982. On DevonianStratigraphy and Palaeontology of the Ardenno-RhenishMountains and related Devonian matters. Courier Fors-

chungsinstitut Senckenberg 55, 498p. 草 举 IkI 举 尽 早 早 I}L 苹

Episodes, Vol. 8, No. 2, June 1985 109