Mich. Comp. Laws § 87.26
The supervisors of the several wards are authorized to perform the same duties in relation to the assessment of property and levying taxes for all purposes in their respective wards, as are imposed by law upon supervisors elected in townships; and they shall have the like powers and perform the like duties in all other respects as supervisors so elected, except as herein otherwise provided, so far as such powers and duties are required to be exercised and performed in their wards; they shall represent their several wards in the board of supervisors of the county in which the city is located, and shall have all rights, privileges and powers of the several members of such board of supervisors: Provided, That any city now having a greater representation upon the board of supervisors of any county than is provided by this act, shall continue to have such representation as it may have at the time of such reincorporation, and if the office of any officer now representing any such city upon the board of supervisors is abolished by this act, the council of such city may annually appoint some suitable person, being a resident elector of such city, to represent the city upon the board of supervisors in the place of such officer whose office has been abolished.
MCL 87.26