Appeal The judge denied the defendant’s motion under G. L. e. 278, § 29C, that he be permitted to withdraw his plea of guilty to so much of an indictment, charging him with murder in the first degree, as charged murder in the second degree; that his sentence under G. L. e. 265, § 2, be revoked; and that he be allowed to stand trial. The denial of the motion rested in the discretion of the judge. Commonwealth v. Sitko, 346 Mass. 765, and cases cited. Commonwealth v. Abboud, 346 Mass. 765. Although the case is not properly before us in any one of the several permissible ways recognized and discussed in Guerin v. Commonwealth, 337 Mass. 264, 266-268, we have, nevertheless, in our consideration of the case, studied the record and the transcripts in the successive proceedings and conclude that the action of the judge was eminently just. We disregard the “bill of exceptions” which was never allowed (Commonwealth v. Robinson, 295 Mass. 471, 472-473) and the “assignment of errors” which does not relate to any exception saved by the defendant. Commonwealth v. Gray, 314 Mass. 96, 102. We treat the defendant’s “appeal” as an effort to impeach the judgment upon matter of law apparent on the record. Guerin v. Commonwealth, 337 Mass. 264, 266. We And no error in this respect or otherwise.