Found this under a piece of fallen silver maple bark in the yard. Not sure if it was there before or after it fell off the tree. It is the size of a very large cotton ball. The center is full of a lot of eggs that are easier to see when they roll around while tilting the bark. I should have taken a video instead. I'm thinking spider eggs, maybe like an orb weaver? I put it back in the garden bed upside-down to protect it. Any ideas? I'm in northern Illinois... not sure why it isn't shown by my username today.