The judge shall examine the jurors who appear, and if more than twenty-four petit jurors who are qualified and not subject to any of the disqualifications provided in this Act, shall appear and remain after all excuses are allowed, the court may discharge by lot the number in excess of twenty-four. If for any reason the panel of petit jurors shall not be full at any time the clerk of such court may again repair to the office of the county clerk and draw in the same manner as at the first drawing, such number of jurors as the court shall direct, to fill such panel, who shall be summoned in the same manner as the others, and if necessary, jurors may continue to be so drawn and summoned from time to time until the panel is filled. In case a jury is required in such court for trial of any cause, before the panel is filled in the manner herein provided, the court shall direct the sheriff to summon from the bystanders, or from the body of the county, a sufficient number of persons having the qualifications of jurors, as provided in this Act, to fill the panel in order that a jury to try such cause may be drawn therefrom, and when such jury is drawn, the persons selected from the bystanders or from the body of the county to fill the panel and not chosen on the jury, shall be discharged from the panel and those who are chosen to serve on such jury shall also be discharged from the panel at the conclusion of the trial: Provided, that persons selected from the bystanders, as provided in this section, shall not thereby be disqualified or exempt from service as jurors, when regularly drawn by the clerk for that purpose, in the manner provided in this Act.