Wildlife Spotting

Unknown bulb accidentally dug up when cleaning out flower bed. About 2.5 inches across what I think is the flat bottom. It seems so strange to me, and I certainly don't remember planting it! It is in a bed with some star-gazer type lilies, day lilies, jack in the pulpit, false solomon's seal, Dutchman's breeches, tulips, vinca minor, hostas, several types of fern and rhododendron.