Well I'm puzzled by these small pumpkin shaped seed objects too as I pass them on every flush, but much fewer on this one, my 7th flush which I completed on Friday. I did retrieve one and squeezed it with a plastic spoon and it was white inside just as I would imagine a seed, so I am completely mystified. I'm moving house on Tuesday and I had to defrost my freezer today. I threw away my jar of flush stones because it seemed too weird to pack them for a move! I feel I have lost my evidence. More stressful than moving!