original description(ofBittium johnstonae Bartsch, 1911)Bartsch, P. (1911). The Recent and fossil mollusks of the genus <i>Bittium</i> from the west coast of America. <em>Proceedings of the United States National Museum.</em> 40 (1826): 383-414, pls 51-58., available online athttps://www.biodiversitylibrary.org/page/15845645 page(s): 387, pl 53, fig. 6 [details]