Invertebrate or shell?

[Philip Ogley]

I recently came across this specimen in a chalk cliff in Normandy, France, near the town of Livarot. I was wondering if anyone could advise me what it might be? Fish, or shell, or something else?

In advance, thanks. 

[Fossildude19]

Size?

And shells ARE invertebrates. 

But these do look like shell imprints to me.

[Rockwood]

Pectinid bivalve shell would be my guess here. There appear to be sponge borings in it is why I think shell as opposed to impression. 

[rocket]

definitely a shell, perhaps an oyster (Lopha-type) or part of a hugh Chlamys-type

Edited March 8 by rocket

[fifbrindacier]

I agree with @rocket.

I've consulted your other post and saw you spoke of Livarot and that the fossilisation of your pecten was the same. So i checked and saw that the fossils of Livarot-pays-d'Auge were Upper Cretaceous.

So that confirm that your fossil could be a kind of Lopha.

Edited March 8 by fifbrindacier

[Philip Ogley]

Thanks to everyone.

So, something like a cockscomb oyster.

It was adjoined the same piece of rock as my previous post, which was identified s a Neithea Bivalve.

[Philip Ogley]

This is a much better image with the neithea bivalve beside it. (same piece of rock)

The oyster bivalve is about 2 x 3 cms 

 

[Rockwood]

I'm going to have to switch to oyster too. The shape does have more of a water wave like look than that of Pectinid ridges.