My paternal grandfather- Casto Martino b. 1897, was supposedly a stowaway on board a ship from Naples to US which arrived on Aug. 26 1911. I do have his naturalization index card(1918) and passport application (1922), which states his arrival in the US(Canopic, White Star Lines, Aug. 26, 1911, but cannot find a record from his original arrival. Canopic records on Ellis Islands website don't show 1911. I am assuming he came through there, but not positive.
Any ideas where to look next?