Staten Island artist Joe Reginella is known for fictional memorials and urban legends. His latest piece, “Watery Graves,” imagines mobsters dumped into New York Harbor in “cement shoes.” The monument is tied to the earlier “Staten Island Ferry Octopus Disaster of 1963.” Reginella says the new work continues his series of invented New York history. He also creates fake newspapers, documentaries and brochures to support the stories. A real monument he made in 2004 honors the firefighters hoisting the American flag at Ground Zero.