Filling of vacancies.- All vacancies among the members (other than ex-officio members) of any authority or other body of the University by reason of death, resignation or otherwise shall be filled, as soon as conveniently may be by the person or body who appointed, nominated, elected or co-opted the member whose place has become vacant, and the person so appointed, nominated, elected or co-opted shall be a member of such authority or body for the unexpired portion of the prescribed term: Provided that pending the filling up of such vacancies by appointment, nomination in the manner aforesaid, the vacancies (other than a vacancy in the Senate may, if the authority or body of the University so decides, be filled by the co-option of any person qualified to fill such vacancy under the provisions of this Act, and any person so co-opted shall hold office as a member of such authority or body until a person is appointed, nominated or elected thereto in accordance with the provisions of this Act.