After the selection of a jury in the trial of a criminal case, in which the accused has participated (assuming from the question under review that the defendant in the instant case did partieipate in the selection of a jury), and after the introduction of evidence upon the merits of the ease has commenced, the defendant will be deemed to have waived formal arraignment, and' it' is then too late for him to demur; and the court did not err in refusing to allow the defendant to demur, nor in overruling the motion to quash.