About the size of a strawberry, this looks like an incomplete yet incredibly intricate paper wasp nest. What do you think? Isn't it amazingly beautiful and intricate when enlarged on the scanner?!
I found this on the floor of our solarium while watering some plants. I'd noticed it over the winter attached to the frame of the openable skylight, far out of reach. It probably got knocked down when the skylight was opened during last week's heat wave.
Compare this to the pieces of another kind of wasp nest.