Collection location: Albion, Mendocino Co., California, USA [Click for map]
First time I had seen these. I was told they came from near the airport. Just big clumpy balls, the young smaller ones had pinkish tones, the older ones are darker. The insides are kinda colorless. They are kinda like rubber balls, and can actually bounce. The bit out of the last photo is really a bite, the squirels had been nibbling on the older ones.