Holes in Stones 3rd.....

I found out the holes are made definitely by living organism!
They live in and from the limestone.
alas I only found a german version, but the Pictures tell the Story as well.....click here

Holes in Stones 2nd.......

Looks to me like made by some living organism......
What do you think?

Holes in Stones....

I have been in Croatia, Istria, for some days.....

and as always I could not resist to pick up several stones at the beach!
I love the bizarre form of these "wormy" stones . The holes are made by living organismn, but I

must confess that I don´t know exactly who`s the causer. Maybe anybody knows....would be great if anyone living by the sea could give an answer ?

...I also found some sepia backs and thought of ossa-sepia-cast.....we will see...