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From the 1950s onwards, long running inventories have been made of the fossil shells from the Dutch coasts. In these inventories amateur collectors and professionals worked together to establish the species identities and occurrences. Currently about 700 species of fossil shells are known from the Dutch coast. In all these years the NMV facilitated and supported the work. The various arguments underpinning the type of research on ex-situ fossils given by C.O. van Regteren Altena over half a century ago are being reconsidered.We conclude that for many reasons the work on these fossil shells has its merits, above all because of the inspiration it invokes by all those involved.

In this paper we treat the fossil Buccinoidea frorn the Dutch beaches and estuaries. So far we have recognized 31 species. The last inventory frorn 1954 cornprised 14 species. The taxonomie status of several of the groups, including dextral species of Neptunea as well as sorne of the columbellid species is in need of further investigation.

In this paper we treat the fossil Rissoidae from the Dutch beaches and estuaries. So far we have recognised 24 species. The last inventory (Van Regteren Altena et al., 1954) documented 12 species. Most rissoid species derive from Quaternary deposits and some are of Pliocene age. Several taxa that possibly can still be found are shortly treated as well.

Fossil pyramidelloidean species from the Dutch coast are described and figured. We report here 21 species.

The fossil Epitoniidae of the Dutch beaches and estuaries are reported. Nineteen (sub) species are recorded. We were unable to resolve the status of the Cirsotrema fimbriosum/funiculus Group.

Fossil species of Trochoidea from the Dutch coast are described and depicted. This group contains various taxa whose taxonomic status is unresolved. We report twelve species of Gibbula, three species of Jujubinus, one Solariella species and seven Calliostoma species. Several species are treated in open nomenclature, pending further taxonomic work.

We treat fossil cerithoid snails from the Dutch beaches and estuaries. It concerns the Superfamily Cerithioidea (excluding Turritellidae that will be treated in a forthcoming paper). We report 19 fossil Cerithium-like species. The genus Bittium, containing seven species, is the most speciose genus.

A new research project assessing and documenting the fossil gastropods from the Dutch coast is initiated. We aim to involve as many as possible non-professional malacologists and palaeontologists to help us with this project. Identification keys will be presented as an invitation to collectors to check their collections and provide further insights and as yet unrecorded species for our fauna during special sessions. The results will be published in Spirula in the form of papers dealing with a specific family or group. We intend to assemble the complete gastropod fauna, in due course, in a second part of “Fossil shells of the Dutch coast”.

We assessed ‘primitive’ fossil gastropods from the Dutch coast (Patellogastropoda, Fissurellidae, Scissurellidae and Haliotidae). The last inventory in 1954 produced eight species; here we increase the number to seventeen, including six species of patellogastropod snails, nine fissurellid snail species and two scissurellid species. Two species treated here in open nomenclature are possibly new to science. The occurrence of two species (Tectura testudinalis and Haliotis tubercularis) requires confirmation. We are uncertain about the origin and age of an apparent fossil Scutus spec.

Small fossil shells were recovered in sieved residues from three localities in streams around the village of Chaam. The composition of the fauna, containing several valves of Ervilia, does not match those of Neogene or Paleogene faunas from adjacent Belgium. It does not appear likely that the fossil shells have been introduced accidentally by man. We suspect the fauna to have derived from Quaternary fluvial deposits that incorporated (now-eroded) Neogene deposits in adjacent Vlaanderen (Belgium).

Iolaea amazonica spec. nov. is described from the Miocene Pebas Formation of Peruvian Amazonia. This species adds to three other pyramidellids, two mesogastropod species and two bivalve species that represent (restricted) marginal marine intervals in the late Middle to early Late Miocene of Western Amazonia.

A molluscan faunule from the Miocene Cumaca Formation of the western margin of the Tuy Basin (Venezuela) is described. The fauna yields two species of freshwater snails and a single terrestrial snail species. Tryonia vivasi nov. spec, is described from the fauna, and its biogeographical significance is discussed.

Two new records of Mytilus galloprovincialis Lamarck, 1819 from the Limfjorden in Denmark and the Jadebusen in Germany show that its northerly distribution limit is further north then commonly assumed.

Previously all mussel species from the Dutch coast have been identified as Mytilus edulis. Over the past few years M. galloprovincialis has been added, but here also recent material of M. trossulus is reported. These three species are also known as fossils from the Dutch beaches, together with a fourth species, M. antiquorum.

Een kleine molluskenfauna, grotendeels van Vroeg Pleistocene ouderdom, uit de Oosterschelde nabij Schelphoek wordt gerapporteerd. De fauna wordt vergeleken metfauna ’s uit de nabijgelegen Deltadienstboring ‘Schelphoek Op zaterdag 31 augustus jl. werd de jaarlijkse bottenvistocht ‘Kor & Bot’ gehouden. Deze tocht, die dit jaar voor de 52ste keer werd gehouden, houdt een dag varen in met de Zierikzee (ZZ)10 van de familie Schot op de Oosterschelde. Onder toeziend oog van de burgemeester van Schouwen Duiveland wordt gevist naar fossiele botten van (meest) Vroeg Pleistocene zoogdieren. Behalve fossiele botten komen er ook vele levende zeebeesten mee omhoog, zoals kreeften, mossels, wulken en andere zaken die als ‘comestibles’ dienst doen, alsmede vele kilo’s slangesterren, zeesterren en ander schoon grut. Dit jaar was de eerste auteur aanwezig met de bedoeling inzicht te krijgen in het voorkomen van fossiele mollusken op de bodem van de Oosterschelde. Met de door Joop van Veen enkele jaren geleden geïntroduceerde de muizenhuis, een stalen buis met een zeef die aan de sleepnetten worden gehangen, werd het mogelijk om sediment en schelpen aan boord te halen die voorheen door de grofmazige kor heen glipten. Al met al heeft de dag een redelijk rijke fauna, voornamelijk van Vroeg Pleistocene ouderdom (vermoedelijk Tiglien) opgeleverd. Het materiaal is matig geconserveerd, veelal afgerond, en heeft meestal een typische geelbruine en soms blauwige kleur. Verder werden ook nog enkele schelpen van Jong Pleistocene en Holocene ouderdom gevonden.

The current state of the activities for the publication of the book ‘The fossil shells of the Dutch beaches and estuaries’ is sketched, and an outlook for the remainder project, up to the expected publication in 2004 is given. Many malacologists (both amateurs and professionals) are involved in this project, and this contribution aims to provide an update..

The taxonomic composition and palaeoecological signature of molluscan faunas from the Miocene Pebas Formation of Peruvian Amazonia are assessed. The Pebas fauna is almost entirely made up of extinct, obligate aquatic taxa, and is dominated in numbers of species and specimens by endemic cochliopine hydrobiid gastropods and pachydontine corbulid bivalves. Molluscan assemblages are defined and linked to depositional environments. Isotope data from the shells indicate freshwater settings during deposition of the Pebas Formation, with the exception of a few incursion levels that were deposited under oligohaline-mesohaline conditions. Faunal and isotope geochemical data point to a large, long-lived freshwater lake system at sea level with swamps and deltas, open to marine settings in the north (Llanos Basin). Sedimentological data and ichnofossils point to (restricted) marine settings. These different interpretations are discussed, and it is concluded that faunas (including ichnofabrics) from evolutionary isolated and longlived systems cannot be assessed in a straightforward actualistic mode, using taxa from non-long-lived environments for comparison. Aspects of Lake Pebas are compared with modem depositional environments. Lake Pebas is among the largest and longestlived lake complexes in Phanerozoic history; it was an important stage for the evolution of endemic molluscan and ostracod faunas. It may have played some role in the transition of marine biota to Amazonian freshwater environments during the Miocene, and likely was an important, hitherto unrecognised, dispersal barrier for terrestrial organisms in northwest South America during the Miocene.

An Eemian mollusc fauna of 57 species is reported from clayballs washed ashore on the beaches of Texel. The occurrence of the clayballs is related to recent beach suppletions. Five species are new to the Dutch beaches, but have previously been reported from Eemian intervals in boreholes and from suppletion terrains in the surroundings of Amsterdam and Amersfoort.

A Middle to Late Pliocene mussel from the southern North Sea Basin referred to previously as Mytilus edulis forma giganteus Wood, 1874, is here reassigned to the genus Perna Retzius, 1788. The name of the forma giganteus has proved to be a junior homonym; hence the species is here renamed P. woodi. It is characterised by, amongst other features, a near-exclusively aragonitic shell, in contrast to species of Mytilus, which have a predominantly calcitic shell. Almost all Cainozoic mussels from Europe generally placed in Mytilus should be reassigned to Perna. Similarities of these to the Pacific genus Crenomytilus Soot-Ryen, 1955, and the use of specific shell characteristics in the generic placement of mussels are discussed.

Mytilus antiquorum J. Sowerby, 1821, is recorded from the Coralline Crag Formation of East Anglia (UK) and the Lillo Formation (Oorderen, Kruisschans and Merksem members) of the Antwerp area (Belgium). The species is diagnosed on the basis of newly collected material and differentiated from modern European mussel species. The presence of M. antiquorum in the southern North Sea Basin is restricted to the Middle (Piacenzian) and early Late Pliocene (Gelasian). A possible occurrence of the species in the latest Pliocene of northern Greenland is discussed. A second Middle- Late Pliocene North Sea Basin species, tentatively referred to as M. edulis forma giganteus Wood, 1874, is diagnosed and discussed. The systematic status of this species remains unresolved. In the Late Pliocene, a third mussel species occurs in the area, tentatively identified as Mytilus ?trossulus Gould, 1850.

Two extant hydrobiid species from the lower Tapajos river of Brazil are redescribed. Potamopyrgus amazonicus Haas, 1949, is assigned to the genus Dyris Conrad, 1871. At least eleven species from Miocene deposits of Western Amazonia are assigned to Dyris, a genus that was previously assumed to be extinct. The apertural features of Sioliella effusa Haas, 1949, are considered indicative of a close relationship to Miocene Amazonian taxa formerly assigned to Eubora Kadolsky, 1980. Sioliella ovata spec. nov., a Miocene species resembling S. effusa is described. The two Tapajos species can be regarded as relicts of a speciose, endemic, Miocene Western Amazonian molluscan fauna.

Odostomia nuttalli spec. nov. and O. cotuhensis spec. nov. are described from the Miocene Pebas Formation of Peruvian and Colombian Amazonia. A third pyramidellid snail is also diagnosed. These species are indicators for marine influence in the late Middle to early Late Miocene of Western Amazonia. Some ecological implications are discussed.

According to Kadolsky (1995) there seems to be no conchological characters that warrant a distinction between Mytilopsis and Dreissena. It is therefore proposed to assign both Dutch dreissenoid species (viz. D. polymorpha and M. leucophaeata) to the genus Dreissena.