These are the equivalent Merchant Navy and Royal Navy ranks officially recognised by the British Government in the Second World War.
[1] Naval Auxiliaries were members of the Royal Fleet Auxiliary and crews of Admiralty cable ships or merchant ships or commissioned rescue tugs requisitioned by the Royal Navy and coming under naval discipline.
Purser (2,501-10,000 tons)Purser (Naval Auxiliary; up to 2,500 tons)Assistant Purser (Naval Auxiliary; 2,501-10,000 tons if only two pursers carried)Senior Assistant Purser (Naval Auxiliary; up to 2,500 tons)Junior Assistant Purser (Naval Auxiliary)Chief Steward (passenger ship over 10,000 tons or passenger ship 2,501-10,000 tons if no Purser carried)