In 1877 three stones were found in a cavern on Rodrigues, each near a Rodrigues solitaire skeleton, and were inferred to be the gizzard stones mentioned by Leguat. One of the stones was examined and found to be dolerite: somewhat rough, hard and heavy, , but hardly flat on one side as described by Leguat. This could be due to its association with a young individual. Although Leguat asserted that the bird hatched with the gizzard stone already inside, in reality adults most likely fed the stones to their hatchlings.