Through the kindness of Dr. Thomas R. Waller, Smithsonian Institution, Washington (USNM), I received a collection of 28 Ensis samples (54 specimens/fragments) from the Miocene of Virginia, Maryland, North and South Carolina, with one sample from the Post-Pliocene. Conrad was the first to work on the subject, describing two fossil species in 1843, Solen directus and S. ensiformis, both belonging to the genus Ensis. After him Dall studied Miocene material of Ensis directus (Conrad), supposing it to be conspecific with the Recent Atlantic form which still bears that name. As far as I can trace, very little systematical work has been done since, the identifications being almost entirely based on Conrad’s views.