The provisions of 3 V.S.A. §§ 257-259 shall apply to vacancies that may occur in the membership of said Commission from this State, and to the power of removal of any such commissioner; except that if a vacancy occurs among such membership, either by death, resignation, removal, or otherwise, between sessions of the General Assembly, the Governor shall have power to fill such vacancy by appointment until March 1 of the next biennial year.