“ It is certainly within the power of a duly advised defendant, before pleading guilty as a second offender, to raise the constitutional invalidity of the first sentence so as to secure opportunity appropriately to challenge such invalidity. Nothing that is herein decided precludes petitioner from raising a denial of his constitutional right upon a record that discloses circumstances other than those before us. An order on such a motion is now reviewable by the New York Supreme Court and in certain instances by the New York Court of Appeals. ”

“ The circumstances are these. On July 15, 1938, Gayes, then a lad of 16, was arraigned in the County Court of Monroe County, New York, upon an indictment charging burglary in the third degree and petty larceny. According to the record of conviction, he was asked, in accordance with the requirement of § 308 of the New York Code of Criminal Procedure, whether 'he desired the aid of counsel,' and he answered 'No.' [1] Imposition of sentence was postponed to July 28. ”

“ The guiding principles bearing on the general problem have been set forth in the opinion in Foster v. Illinois, 332 U.S. 134, 67 S.Ct. 1716, just decided. Insofar as the facts of this case present a particular variant, they are controlled by our decision in Canizio v. ”