Took Socks for a walk on a beach.

Hmmmm still problems: after zooming at near top speed the bitch {sigh} picked up a rock and started running with it in her mouth with me aghast at the thought of what the rock could do to her beautiful sharp white teeth. Trying to call her to me did not succeed—she did not come near enough for me to clip the lead back on.

After some thought I decided to keep walking. Socks had a good time but the beach SUCKS for walking (but is a rare lead–off beach.)

Instead of rocks she picked up shells, big ones, crunching them a bit. No probs.

The sky getting increasingly dark I called her and, amazingly, I could clip the lead onto her collar and we headed back. Lots of shells on the beach. On the way back, bitch on the lead, I looked at the shells.

They were mostly bivalves. I looked for something. Some shells had big holes but these could have been caused by erosion in the tidal wash. One had a small hole near the top. I then looked while walking back to the exit from the beach. Only found one gastropod. What is the relationship with  the hole in the shell?

What condition would be needed for the tideline of shells to become fossiliferous rock?

Anyone?