Gerald Felton filed an untimely notice of appeal from the district court's denial of his motion for reduction of sentence. We dismiss for lack of jurisdiction. The time periods for filing notices of appeal are governed by Fed. R.App. P. 4. These periods are "mandatory and jurisdictional." Browder v. Director, Dep't of Corrections, 434 U.S. 257, 264 (1978) (quoting United States v. Robinson, 361 U.S. 220, 229 (1960)). Criminal defendants have ten days within which to file in the district court notices of appeal from judgments or final orders. Fed. R.App. P. 4(b).* The only exception to the appeal period is when the district court extends the time to appeal under Fed. R.App. P. 4(b) upon a showing of excusable neglect.

The district court entered its order on March 20, 1996; Appellant's notice of appeal was filed on October 11, 1996. Appellant's failure to obtain an extension within the prescribed time frame leaves this court without jurisdiction to consider the merits of Appellant's appeal. We dispense with oral argument because the facts and legal contentions are adequately presented in the materials before the court and argument would not aid the decisional process.