There is no accounting for nicknames, but "Lefty" Merrill writes and drinks with his right hand.
James Cagney states, as Lefty Merrill: "What do I know about grapefruit? I never even saw a grapefruit!" One of Cagney's best known scenes is smashing a grapefruit into Mae Clarke's face in The Public Enemy (1931).
James Cagney would play a character who orchestrates a dance contest the next year in Here Comes the Navy (1934).