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GEOLOGICA CARPATHICA, APRIL 2006, 57, 2, 123—130

Early Sarmatian biota in the northern part of the Danube

Basin (Slovakia)








Geological Survey of Slovak Republic, Mlynská dolina 1, SK-817 04 Bratislava, Slovak Republic;;


National Museum, Václavské nám. 68, CZ-115 79 Praha 1, Czech Republic;

(Manuscript received February 14, 2005; accepted in revised form October 6, 2005)

Abstract: Lower Sarmatian molluscan (gastropod, bivalve), foraminiferal, ostracod, bryozoan and algal taphocenotic
associations occur in northern part of the Danube Basin in SW Slovakia. Bryozoan associations are dominated by
stenohaline forms such as Hippopleurifera cf. semicristata (Reuss), Hippadenella regularis (Reuss) and Celleporina sp.
Their occurrence along with other paleoecological and isotopical indicators gives ground for inferring a local persistence
of full-marine conditions in this part of the Lower Sarmatian Central Paratethys.

Key words: Early Sarmatian, Central Paratethys, stratigraphy, paleoenvironmental reconstruction, Mollusca,
Foraminifera, Ostracoda, Bryozoa.


During Miocene times the Danube Basin was a part of
the Central Paratethys. From the Late Badenian to Early
Sarmatian the sea level dropped rapidly in the whole
Paratethys and the area lost connection with the open sea
(Rögl & Steininger 1983). This isolation resulted in re-
duction of salinity, causing extinction of stenohaline or-
ganisms, corals, radiolarians and many species of
molluscs, foraminifers, ostracods and calcareous nanno-
plankton. New paleoecological and isotopic studies (La-
tal et al. 2004; Piller & Harzhauser 2005) indicate that
the isolation of the basin did not result in decrease of sa-
linity everywhere. A new transgression started at the be-
ginning of the Sarmatian and formed a large
epicontinental basin situated between the Alps in the
west and the Aral Sea in the east (Paramonova 1994). The
basin was characterized by high alkaline waters oversat-
urated with carbonate (Pisera 1996), by uniform environ-
mental conditions (Rögl 1998), and by episodic
connections with the Mediterranean (Paramonova 1994).

In the West Carpathian basins (both the Vienna and

Danube Basins), the regression at the boundary between
the Late Badenian and Early Sarmatian formed a fresh-
water to brackish lake and Badenian sediments were
eroded (Hudáčková & Kováč 1993). During Early Sarma-
tian transgression, the sedimentation started with shallow
water deposits (Kováč 2000) characterized by occurrence
of large foraminifers of the Elphidium reginum Biozone
in the sense of Grill (1941).

Characteristics of Sarmatian sediments of the

northern part of the Danube Basin

The basal member of the Vráble Formation (Priechodská

in Harčár et al. 1988) of Early Sarmatian age starts with

freshwater gravels and sands containing redeposited Bade-
nian marine foraminifers.

These sediments are passing both laterally and vertical-

ly into variegated pelitic sediments without fossils. They
are overlain by fine-grained sands and sandy clays with
abundant carbonized parts of plants, and higher up, by
greenish-grey calcareous clays with rich assemblages of
molluscs, in which Mohrensternia cf. inflata (M. Ho-
ernes),  M.  styriaca Hilber, M. cf. sarmatica Friedbberg, M.
banatica Jekelius, Pseudamnicola  sarmatica  sarmatica
Jekelius,  Acteocina lajonkaireana  lajonkaireana  (Bas-
terot),  Hydrobia stagnalis andrusovi Hilber dominate, and
with associations of foraminifers consisting of Elphidium
reginum (d’Orbigny), E.  crispum (Linné), E. cf. josephi-
num (d’Orbigny), E.  aculeatum (d’Orbigny) and Nonion
cf.  bogdanowiczi  Voloshinova (Mořkovský 1960).

Middle Sarmatian sediments of the Elphidium haueri-

num Biozone (Grill 1941) in the Vráble Formation are rep-
resented by basinal pelites and marginally by sand.
Basinal sediment includes greyish, greenish to grey and
blue-greenish clays. Locally, the clays are rusty in colour,
typically without any microfauna. Only a few foramini-
fers  have been determined: Elphidium cf. hauerinum
(d’Orbigny),  E.  crispum (Linné), Ammonia beccarii (Lin-
né) and Nonion cf. bogdanowiczi Voloshinova (Dlugi &
Svoboda 1958; Mořkovský 1960). The marginal develop-
ment is characterized by a layer of gravels to coarse-
grained sands about 5 m thick, but thinning out towards
the margin of the basin (Mořkovský l.c.).

The Upper Sarmatian part of the Vráble Formation com-

prises pale greenish to greyish clays, frequently with rusty
mottled calcareous portions in their basal parts and fine-
grained to medium-grained sand, which often passes to ru-
daceous sand to gravel at the top. The following fauna has
been determined from Upper Sarmatian sediments: foramin-
ifers  Nonion granosum (d’Orbigny), N.  bogdanowiczi Vo-
loshinova,  Ammonia beccarii (Linné), Elphidium ex gr.

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macellum (Fichtel et Moll), ostracods Hemicytheria lören-
they (Méhes), gastropods Pirenella and Hydrobia, and
bivalves  Cardium (Čermák 1969; Lunga 1964; Moř-
kovský 1960).

In the deeper part of the basin, a regressive trend may be

indicated in Upper Sarmatian sediments with coaliferous
clays and wooden lignite (Mořkovský l.c.).

The Dubová section

A very instructive and fossiliferous section near  Dubová

village was excavated during construction works for dump
place below the eastern slopes of the Malé Karpaty Mts
about 10 km north of the town of Pezinok (Fig. 1). Grey to
greenish clays of the Vráble Formation contain thin tempes-
tite intercalations of molluscan shell debris.

Abundant fauna of molluscs (gastropods, bivalves), for-

aminifers, ostracods, bryozoans and calcareous cysts of al-
gae  Chalmasia morelleti Pokorný has been found in these
shell beds.

Fig. 1. Geographical sketch map of the Dubová locality.

Table 1: Fauna determined from the Dubová locality.

List of species found


Actecina lajonkaireana lajonkaireana (Basterot)
Calliostoma angulata spirocarinata Papp
Hydrobia stagnalis (Basterot)
Mohrensternia pseudoangulata pseudoangulata Hilber
Mohrensternia pseudoangulata politioanei Jekelius
Mohrensternia inflata (M. Hoernes)
Mohrensternia banatica Jekelius
Mohrensternia styriaca Hilber
Ocinebrina sublavata sublavata (Basterot)
Pirenella soceni Jekelius
Pseudamanicola immunata (M. Hoernes)


Cardium procarpatinum spinosum (Jekelius)
Ervilia dissita dissita Eichwald
Inaequicostata politioanei suessiformis (Jekelius)
Musculus sarmaticus (Gatujev)
Obsoletiforma obsoleta ghergutai (Jekelius)


Ammonia beccarii (Linné)
Articulina articulinoides Gerke et Issaeva
Articulina problema Bogdanowicz
Bulimina schischkinskayae (Samoylova)
Cycloforina contorta (d’Orbigny)
Cycloforina sp.
Elphidium aculeatum (d’Orbigny)
Elphidium crispum (Linné)
Elphidium fichtelianum (d’Orbigny)
Elphidium josephinum (d’Orbigny)
Elphidium macellum (F.-M.)
Elphidium reginum (d’Orbigny)
Nonion bogdanowiczi Voloshinova
Porosononion granosum (d’Orbigny)
Porosononion  cf. martkobi (Bogdanowicz)
Quinqueloculina akneriana d’Orbigny
Quinqueloculina badenensis (d’Orbigny)
Quinqueloculina boueana d’Orbigny
Quinqueloculina hauerina (d’Orbigny)
Rosalina obtusa d’Orbigny
Schackoinella imperatoria (d’Orbigny)
Porosononion granosum (d’Orbigny)


Aurila mehesi (Zalányi)
Cytheridea hungarica (Zalányi)
Hemicytheria omphalodes omphalodes (Reuss)
Leptocythere tenuis (Reuss)
Loxoconcha schmidi Cernajsek
Xestoleberis glaberescens (Reuss)


Tubulipora cumulus (Sinzow)
Schizoporella tetragona (Reuss)
Hippopleurifera cf. semicristata (Reuss)
Hippadenella regularis (Reuss)
Celleporina sp.

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Eleven species of gastropods and five species of bivalves

have been found in the sediment from Dubová (Table 1).

Mohrensternia is the dominant species among the gas-

tropods,  Ervilia dissita dissita Eichwald dominates
among bivalves (Table 1). According to Papp (1954), such
an association of molluscs is characteristic of the Rissoa
Beds of the Early Sarmatian age (Fig. 2).


Elphidium dominate among the studied foraminifers

(Table 1). This foraminiferal association found at Dubová
is typical of the Early Sarmatian Elphidium reginum Bio-
zone sensu Grill (1941).


Cytheridea hungarica (Zalányi) is the dominant ostra-

cod species, but an additional five species were also deter-
mined (Table 1).

According to the presence of ostracods Cytheridea hun-

garica  (Zalányi) and Aurila mehesi (Zalányi), the fauna

belongs to the Early Sarmatian biozone of Cytheridea
hungarica—Aurila mehesi (Fig. 2), which is well correlable
around the entire Paratethys Basin (Jiříček 1983; Stanche-
va 1990; Zelenka 1990).


No Sarmatian bryozoans have been previously de-

scribed from Slovakia. Our new study has led to the recog-
nition of five species of Bryozoa (Table 1). Large colonies
of celleporid cheilostome of Celleporina sp., along with
colonies of the cyclostome Tubulipora cumulus (Sinzow,
1892) as described by Ghiurca & Stancu (1974) dominate
the studied association.

Material and methods

The samples for detailed study were taken from thin lay-

ers intercalated within the clay, with macroscopically visi-
ble fragments of molluscs. The samples were dried and
subsequently moistened in water several times until their
disintegration and than they were washed on sieve with
0.025 mm mesh diameter. The washed residues were studied

Fig. 2. Biozonation of the Sarmatian based on foraminifers, molluscs and ostracods.

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Fig. 3. Foraminifera. 1  –  Elphidium aculeatum (d’Orbigny). 2 – Elphidium josephinum (d’Orbigny). 3—5 – Elphidium reginum
(d’Orbigny).  6  –  Schackoinella imperatoria (d’Orbigny). 7 – Ammonia beccarii (Linné), 8 – Nonion bogdanowiczi Voloshinova.
9—10 – Porosononion cf. martkobi (Bogdanowicz). 11 – Articulina articulinoides Gerke et Issaeva. 12 – Cycloforina sp. All pictures
were made on a SEM JSM-840 in the Geological Survey of the Slovak Republic by I. Holický. Scale bar 100 µm.

under binocular microscope and fragments of molluscs, for-
aminifers, ostracods and bryozoans were selected.

Bryozoans were, before detailed taxonomic study, mac-

erated in Quaternary “O”

 for about 2—3 days. The sam-

ples with Quaternary “O”

 could be heated for a better

effect of cleaning in a water bath to 80—100 °C. All the

specimens were cleaned in an ultrasonic cleaner before
taking any photos (details see Zágoršek & Vávra 2000).

Foraminiferal and ostracod assemblages were studied by

JSM-840 SEM in the Geological Survey of the Slovak Re-
public, photos were taken by I. Holický. The described
specimens of molluscs, foraminifers and ostracods are de-

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Fig. 4. Ostracoda. 1—2 – Cytheridea hungarica (Zalányi). 3 – Aurila mehesi (Zalányi). 4 – Aurila merita (Zalányi). 5 – Loxocon-
cha schmidi Cernajsek. 6 – Hemicytheria  omphalodes omphalodes (Reuss). 7 – Callistocythere sp. 8 – Xestoleberis glaberescens
(Reuss). All pictures were made on a SEM JSM-840 in the Geological Survey of the Slovak Republic by I. Holický. Scale bar
100 µm.

posited in the Geological Survey of the Slovak Republic
in Bratislava.

Bryozoans were studied and documented by K. Zágoršek

by use of the Jeol type JSM-6400 SEM in the Paleontologi-
cal Department of Vienna University. The specimens de-
scribed are deposited in the National Museum in Prague.

Ecological needs of found species

Mohrensternia and Hydrobia (gastropods) occurred in

the littoral to sublittoral zone at depths up to 30 m, in well
aerated water, with abundant vegetation and salinity lev-
els between 0.9 and 1.8 % (Remane 1958; Švagrovský

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Fig. 5. Bryozoa. 1—3 – Tubulipora cumulus (Sinzow, 1892); note marked concentric growth lines, apertures arranged in fascicles and
porous frontal walls. 4  –  Hippadenella regularis (Reuss, 1874); general view showing wide apertures with characteristic key-shaped
suboral avicularium (visible on right zooecium). 5 – Schizoporella tetragona (Reuss, 1848); detail of a few zooecia with visible char-
acteristic aperture with wide sinus and large oral avicularia with prominent pivotal bar. 6—7 – Celleporina sp.; general view showing
small suboral avicularia, lateral areolar pores and ovicells with semicircular windows. All pictures were made in the Paleontological In-
stitute of Vienna University in SEM Jeol type JSM-6400 by K. Zágoršek. Scale bar 100 µm.

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1960; Iljina 1966). Mohrensternia preferred quiet water
environments (Kowalke & Harzhauser 2004).

The presence of bivalve Ervilia dissita dissita Eich-

wald indicates shallow water with a sandy bottom, Obso-
letiforma lived on sandy to sandy-clay bottoms, and
Inaequicostata sandy-clay to clay bottoms (Paramonova
1994). The occurrence of Chalmasia morelleti Pokorný
through the whole profile indicates a warm climate and
shallow water during deposition of the studied sediments
(Pokorný 1948).

The presence of an Elphidium—Quinqueloculina fora-

miniferal assemblage proves brackish, shallow water. El-
phidium is generally considered to indicate depths of less
than 80—100 m (Walton 1964; Boltovskoy-Wright 1976;
Poag 1981). According to Murray (1973) Schackoinella
imperatoria (d’Orbigny) lived in the shallow neritic zone
up to 50 m deep.

The presence of the ostracods Cytheridea, Aurila, Hemi-

cytheria, Loxoconcha, Leptocythere and Xestoleberis in-
dicates a shallow, brackish water paleoenvironment
(Jiříček 1983).

Bryozoans from brackish environment were described

very rarely. Bobies (1957) was the first (and last up to
now), who mentioned Bryozoa from non-marine sedi-
ments. He described 10 Sarmatian species from Austria,
from which only Schizoporella tetragona (Reuss, 1848)
also occurs in the locality studied.  Ghiurca & Stancu
(1974) described Tubulipora cumulus (Sinzow, 1892)
from brackish sediments of Romania. Pouyet (1973)
pointed out, that Celleporina could also have survived
in water with lower salinity, but it was never reported in
the recent brackish environment. Hippopleurifera cf.
semicristata (Reuss, 1848) and Hippadenella  regularis
(Reuss, 1874) are typical marine species, which indicate
that the bryozoan association studied here could have
lived in the full-marine environment.

Interpretation and reconstruction of the

paleoenvironment of the Dubová locality

Based on ecological requirements of the species and

genera of molluscs, foraminifers and ostracods identified
in the studied association, we can infer that the Early Sar-
matian paleoenvironment at Dubová was shallow littoral
to sublittoral at depths of up to 30 m, with sandy to sandy-
clay bottoms and well aerated water in a warm climate.

Small changes in the original paleoenvironment have

been documented by the qualitative composition of the
mollusc assemblages. During transgression at the begin-
ning of the Early Sarmatian, the sandy sediments with Er-
vilia dissita dissita Eichwald were deposited near the
shore in the zone of wave action (Paramonova 1994).
Short stormy events caused deposition of thin layers con-
taining fragments of this mollusc. Later, the depth in-
creased slightly and fine-grained, pelitic sediments
(clayey sand to clay) were deposited. This environment
was suitable for the gastropods Mohrensternia and Hydro-
bia  and for the bivalve Inaequicostata, which indicate

well aerated, quiet water with a depth of less than 30 m,
and a bottom overgrown by vegetation (Remane 1958;
Švagrovský 1960; Iljina 1966; Kowalke & Paramonova
1994; Harzhauser 2004).

The presence of bryozoans Hippopleurifera cf. semicris-

tata  (Reuss), Hippadenella regularis (Reuss) and  Celle-
porina  sp. indicates a possible full-marine character of the
Lower Sarmatian sea in the region of the northern part of
Danube Basin.

On the basis of the presence and preservation of these

fossils in clayey sediment, we can suppose, that the tapho-
coenosis was transported a short distance from a shallow,
high energy environment (above wave base) with a sandy
bottom, to deeper and quieter conditions on a clay bot-
tom. The occurrence of the fossils in very thin layers as
small fragments supports this hypothesis. The salinity in
these two settings could be different; the shallow water as-
sociation including bryozoans could have lived in almost
normal salinity, while the association with the gastropods
Mohrensternia and Hydrobia  lived in deeper, quiet condi-
tions with lower salinity. Normal salinity in shallow water
environment could be explained by higher evaporation of
brackish water in warm environment or as marine residues
in a brackish basin.


In the northern part of the Danube Basin at the

Dubová locality (Fig. 1) sediments containing rich as-
semblages of molluscs (gastropods, bivalves), foramini-
fers, ostracods, bryozoans and algae were found
(Table 1). On the basis of individual groups of fossils
the sediments were ranged biostratigraphically accord-
ing to gastropods to the Rissoa Member (Papp 1954), to
the  Elphidium reginum Biozone (Grill 1941) on the ba-
sis of foraminifers and to the Cytheridea hungarica—Au-
rila  mehesi Biozone (Zelenka 1990) on the basis of
ostracods (Fig. 2). The occurrence of bryozoans at this
locality represents their first find in Lower Sarmatian
sediments of the northern part of the Danube Basin. On
the basis of the paleoecological pretentions of individ-
ual species of the fossil groups mentioned it may be
stated that sediments at the Dubová locality were de-
posited in shallow water environment during warmer
climate period. The presence of bryozoans Hippopleu-
rifera cf. semicristata  (Reuss), Hippadenella regularis
(Reuss) and Celleporina  sp. pointed to the fact that
character of the environment was probably marine dur-
ing the Early Sarmatian as indicated by recent paleo-
ecological and isotopic studies (Latal et al. 2004; Piller
& Harzhauser 2005).


 Many thanks go to Prof. N. Vávra and

Dr. R. Zetter (Institute of Palaeontology, Vienna Universi-
ty, Austria) for their help with photography and com-
ments. The research was supported by FWF (Fonds zur
Förderung der wissenschaftlichen Forschung, Austria)
through Project P15600.

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Bobies C. 1957: Bryozoenstudien II. Die Bryozoans des österre-

ichischen Sarmats. Jb. Geol. Bundesanst. 100, 1, 81—112.

Boltovskoy E. & Wright R. 1976: Recent foraminifera. III—XVII.

Junk,  Den Haag, 1—515.

Čermák D. 1969: Shallow and medium deep structural exploration

in the Pieš any promontory. MS Archives Geol. Surv. Slovak
Rep., Bratislava, 1—15 (in Slovak).

Dlugi A. & Svoboda S. 1958: Contribution to the biostratigraphi-

cal characterization of the Neogene of the western part of the
Little Danube Lowland. In: Dlugi A., Fischer J., Homola V.,
Janák J., Mořkovský M., Slavík J., Svoboda S., Šmeral J. &
Uhman J. (Eds.): Key well Báhoň-1 in the western part of the
Little Danube Lowland. Práce Úst. pro naftový výskum sv.
12, publ. 43, Brno, 41—58 (in Czech).

Ghiurca V. & Stancu J. 1974: Les Bryozoaires sarmatiens du Parat-

ethys Central. In: Papp A., Marinescu F. & Seneš J. (Eds.): M5
Sarmatien: Die Sarmatische Schichtngruppe und ihr Stratotu-
pus. VEDA, Bratislava, 298—317.

Grill R. 1941: Stratigraphische Untersuchungen mit Hilfe von Mik-

rofaunen im Wiener Becken und den Benachbarten Molasse-
Anteilen. Öl und Kohle (Berlin) 37, 595—602.

Harčár J., Priechodská Z., Karolus K., Karolusová E., Remšík A. &

Šucha P. 1988: Explanations to the geological map of the
north-eastern part of the Podunajská Lowland 1:50,000.
GÚDŠ, Bratislava, 1—114 (in Slovak).

Hudáčková N. & Kováč M. 1993: The Upper Badenian—Sarmatian

events in the area of the Vienna Basin eastern margin. Miner.
Slovaca 25, 3, 202—210 (in Slovak).

Iljina L.B. 1966: History of Black Sea gastropods. Trudy Paleont.

Inst. 11, 3, 3—228 (in Russian).

Jiříček R. 1983: Redefinition of the Oligocene and Neogene ostra-

cod zonation of the Paratethys. Misceliana Micropaleontologi-
ca 195—236.

Kováč M. 2000: Geodynamic, paleogeographical and structural de-

velopment of the Carpathian-Pannonian region in the Mi-
ocene. VEDA, Bratislava, 5—202 (in Slovak).

Kowalke T. & Harzhauser M. 2004: Early ontogeny and palaeo-

ecology of the Mid-Miocene risoid gastropods of the central
Paratethys.  Acta Palaeont. Pol. 49, 1, 111—134.

Latal Ch., Piller W.E. & Harzhauser M. 2004: Palaeoenvironmental

reconstructions by stable isotopes of Middle Miocene gastro-
pods of Central Paratethys. Palaeogeogr. Palaeoclimatol.
Palaeoecol. 211, 157—169.

Lunga S. 1964: Geological report on structural exploaration in the

Pieš any embayment for the year 1963. MS Archives Geol.
Sur. Slovak Rep., Bratislava (in Slovak).

Mořkovský M. 1960: Geologische Verhältnisse im NW Teil des Tr-

navaer Ausläufers der Kleinen Donautiefebene Geol. Práce,
Zoš.  59, 103—117 (in Slovak).

Murray J.W. 1973: Distribution and ecology of living benthic fora-

miniferids.  Heinemann Educatinal Books, 1—274.

Papp A. 1954: Die Molluskenfauna im Sarmat des Wiener Beckens.

Mitt. Geol. Gessel. 45, 1—112.

Paramonova N.P. 1994: History of Sarmatian and Akchagyl bi-

valve mollusc. Trudy Paleont. Inst. 260, 1—212 (in Russian).

Piller W.E. & Harzhauser M. 2005: The myth of the brackish Sar-

matian Sea. Terra Nova 17, 5, 450—455.

Pisera A. 1996: Miocene reefs of the Paratehys: a review. SEMP

Concepts in Sedimentology and Paleontology 5, 97—104.

Poag C.W. 1981: Ecologic atlas of benthic foraminifera of the

Gulf of Mexico. V—VIII. Mar. Sci. International, Woods
Hole/Mass. 1—175.

Pokorný V. 1948: The alga Chalmasia Morelleti n. sp. In the

Czechoslovak Sarmatian. Rozpr. Čs. Akad. Věd a umění, Třída
II, 58, 3, 1—7 (in Czech).

Pouyet S. 1973: Revision Systematique des Cellepores (Bryozoa,

Cheilostomata) et des Especes Fossiles Europeennes. Analyse
de Quelques Populations a Cellopores dans le Neogene du
Bassin Rhodanien. Doc. Lab. Geol. Fac. Sc. Lyon 55, 1—266.

Remane A. 1958: Ökologie des Brackwassers. Die Binnengewässer

221, Stuttgart, 191 s.

Rögl F. 1998: Paleogeographic consideration for Mediterranean

and Paratethys seaways (Oligocene to Miocene). Ann.
Naturhist. Mus. Wien 99A, 279—310.

Rögl F. & Steininger F. 1983: Von Zerfall der Tethys zu Medi-

terran und Paratethys. Ann. Naturhist. Mus.  Wien  85A,

Stancheva M. 1990: Upper Miocene ostracods from northern Bul-

garia. Geol. Balcanica, ser. operum singulorum 5, 5—111.

Švagrovský J. 1960: Die Biostratigraphie des Miozäns und die

Ökologie der Makrofauna der Basisbohrung Sečovce 1. Práce
Výzk., Úst. Čs. naft. dolů 15, 53—93 (in Slovak).

Walton W.R. 1964: Recent foraminiferal ecology and paleoecology.

In: Imbrie J. & Newell N. (Eds.): Approaches to paleoecology.
J. Wiley and Sons, New York, London, Sidney, 151—237.

Zágoršek K. & Vávra N. 2000: A new method for the extraction of

Bryozoans from hard rocks from the Eocene of Austria. Jb.
Geol. Bundesanst. 142, 2, 249—258.

Zelenka J. 1990: A rewiew of the Sarmatian Ostracoda of the Vien-

na Basin. In: Ostracoda and global events. British Micropale-
ont. Soc. Publ.  London, Chapman and Hall, 263—270.