General Clauses Act, 1897
15. Power to appoint to include power to appoint ex
officio
Where, by any 12[Central Act] or Regulation, a power to appoint
any person to fill any office or execute any function is conferred, then,
unless it is otherwise expressly provided, any such appointment, if it is made
after the commencement of this Act, may be made either by name or by virtue of
office.