Sarah,

One of my favorites was in the paleontologic teaching collection at
Stanford University. It was just a clam, preserved in sandstone with both
valves still attached and gaping a little. When you opened the valves,
which had been broken apart, there was a leaf inside. Naturally, our
assignment was to explain how the leaf and clam could both be preserved in
one place. The students also wondered, Was this a herbivorous clam? Or a
clamivorous leaf?

Andrew K. Rindsberg
Geological Survey of Alabama