Dr Williams,
I found what I'm guessing is a turkey egg. I've never seen one in the woods like this before. It was laying in planted pines in Alabama. It is an egg of some type but it appears the hard outer shell never developed. Have you seen this before, and if so is it common?
(http://img.photobucket.com/albums/v395/olesixbeards/P4080176.jpg)
This is the size of a large chicken egg.
guesswho,
I have never heard of it before.