From Dall, 1898, p. 629: “Eocene of the Jacksonian at Moody’s Branch, Jackson, Mississippi; Oligocene of the Bowden beds, Jamaica; Matura, Trinidad; of the Tampa silex beds at Ballast Point, Florida, and on the Chipola River; Pliocene of Limon, Costa Rica, and of the Caloosahatchie marls; Pleistocene of the Antilles generally; and recent from Cape Hatteras to Barbadoes and the Gulf of Campeachy. The fossils are identical with the recent shells in every particular, and there can be no doubt that this species has existed continuously in the Antillean region since the Upper Eocene.”
