Sentence:  The Officers, Non-Commissioned Officers, Bombardiers, Fifers, Gunners, Private Men, and Boys of the Royal Marines belonging to Her Majesty's Ships or Vessels, whether entered on the Ship's Books as part of the complement, or borne as <WSD>supernumeraries</WSD>, except when borne for a passage for service on shore, shall be considered entitled to the same advantages as the rest of the Ship's Company. 
Meaning of the word marked with <WSD> tags:  A person who works in a group, association, or public office without forming part of the regular staff (the numerary). (from early 17th c.)