The commission shall meet at the regular place for holding such meetings, at ten a.m. on the first day of January after its election, at which time the newly elected commissioners shall assume the duties of their office. Thereafter the commission shall meet in legislative session at least twice each month and in administrative session at least once each week, at such times as are prescribed by ordinance or resolution, but no legislative business shall be considered or acted upon at administrative sessions. Upon written request of the chairman or of any two members, special legislative sessions of the commission shall be called by the clerk. Any such request shall state the subjects to be considered at such special meeting, and no other subject shall be considered.