Michael's "Cavity"

I decided to stray from the usual suspects on this one.  Tooth cavities are no fun unless you have an X-ray machine and I do not.
The kind of cavity they talk about in an airport search did not work for me either.  I had taken some pictures with closeup lenses in my back yard this weekend.  Found a set for my daughter and decided to dig mine out for a change.  Lilies have a cavity where the stamen come out of the flower.  Good enough for me!