These are interestingly textured and curiously shaped with an intriguing bulge at the distal end as though a bladder inside was expanding. Dirr observes that the seeds germinate readily with no pre-treatment. We will have to give them a try.
This particular plant is in the Coastal Plain section of Fern Valley. I missed the flowers this year and, judging from the quantity of fruit, I missed a good year. The floral display is spectacular, no thanks to the flowers themselves, which are inconspicuous, but because of the large pink, white, and rose colored bracts.
Pinckneya is a tree of the far south, native to north Florida and South Georgia. Unlike, say Franklinia, you don't hear about wonderful specimens in the warmer parts of New England. I think we really are about as far north as it goes. We had lower temperatures last winter than we've had for a while but nothing like 2F that Dirr relates killed a plant in his garden, though ours are likely more cold acclimated than his plants in Georgia. This is the happiest I have seen our plants so there's every reason to assume a good floral display for next year.