Name was recorded reversed. His one portrayal here is the Gypsy in the Mehta Trovatore of 1971 (recording 9264), which is the Met broadcast of Sat 13 March 1971; the Met performance database for that night (https://archives.metopera.org/MetOperaSearch/record.jsp?dockey=0374585) lists "Gypsy - Herman Marcus", and his Met career page runs 1970-1997 under that name.

Migration: a zero year, month, day or OperaClass id meant the value was unknown, not that it was zero. Set to null.