This video from the USA is called Introduction to Fossil Sea Shell BRACHIOPODS pt 1 of 4.
Today, the natural history museum, jointly with the Dutch Malacalogical Society, had a theme day on seashells and snails.
The lectures were in the auditorium, with many horns and antlers of deer, antelope, and cattle species hanging on the walls.
The second lecture of today was on fossil seashells of the Dutch beaches and estuaries.
It was by Frank Wesselingh, at the moment working at a dissertation on fossil seashells of the Amazon region.
But he works on their Dutch equivalents as well.
He said there were about 700 fossil mollusc species found so far in The Netherlands: over 300 gastropods, 335 bivalves, 8 chitons, 7 scaphopods.
For comparison: at present there are nearly 300 mollusc species in The Netherlands, about half of them marine.
Some fossil species are tens of millions years old; some just a few thousand.
At many places along the Dutch coast, these fossils can be found.
Traditionally, Zealand in the south west is the best known.
But now, other places are being discovered.
Though beaches between Wassenaar and Zandvoort do not have many fossil shells.
In Zealand, a well known fossil is Megacardita planicosta from the Eocene period.
Also, from the Pliocene, Spisula inaequilatera; and Chlamys princeps.
The Kaloot beach in Zealand is famous for its fossils.
Unfortunately, now it is threatened by economic interests.
Among its shells are Aequipecten angeloni from the Miocene.
More to the north, and later, from a hotter age between ice ages, is Solen marginatus.
During ice ages, more northern species, like Astarte borealis prevailed.
Research of Dutch fossil shells led to discovering species new to science; like Yoldia heeringi and Pleuromeris moerdijki.
Scaphopods: Eocene-Oligocene Paleontology of Lincoln Creek, USA: here.
Drakozoon lived in the ocean during the Silurian Period, 444 to 416 million years ago, and today’s model hints at how it lived: here.