Aut cum scuto aut in scuto
Looks like a snail towards the end nearest the viewer.
Yes! I found a fossil vertebrae of some aquatic mammal in the sandstone at Cape Kiwanda on the Oregon Coast. I went back several days later, with a hammer and chisel, and extracted it. Forty some years ago. Probably illegal to do now. Come get me. I still have the evidence.
When I lived in Florida I used to cruise the banks of the Intercoastal Waterway up north of Daytona, especially after heavy rains. I have a bunch of fossilized mastodon teeth sitting on my bookshelf......