The Supervisor of Elections shall send in sealed packages for each polling district the ballots prepared by him to the several boards of elections so as to be received by them at least two days prior to the day of the primary or election. Each package shall be marked on the outside, clearly designating the election district and polling district for which the ballots are intended and the number of ballots of each kind enclosed. If there is more than one polling place for a polling district, there shall be sent a sealed package of ballots for each such polling place, and each such package shall also be marked with the designation of the polling place for which it is intended. The Supervisor of Elections shall keep a record of the time when, and the manner in which, the several packages were sent to the boards and a record of the number of ballots of each kind so forwarded.