Subsequent panels of petit jurors for two weeks each shall be called as the judge or judges may determine during the term, and at least ten days before such subsequent panel, the judge or judges, as the case may be, shall proceed as aforesaid to the office of the jury commissioner, and the jury commissioner shall, in the presence of such judge or judges, draw in the same manner such number of names as such judge or judges shall direct as petit jurors for such subsequent two weeks period of that term for jury service. The persons so drawn shall be notified and summoned the same as those drawn for the first two weeks. The judge or judges may, by order, defer the drawing and reporting of jury panels for service after the first two weeks of the term for such period of time as they may determine and in such order or orders may fix the number of panels to be drawn and the number of jurors to be drawn for each panel. During the term the jury commissioner shall draw, notify, and summon other petit jurors in the manner hereinbefore provided as often as the length of the term may require and the judge or judges direct. The provisions of this section shall not be mandatory in counties having a population of less than sixty thousand inhabitants.