Exhibit 2.1 AMENDMENT NO. 1, dated as of September 6, 2005 (this "AMENDMENT"), to the AGREEMENT AND PLAN OF MERGER, dated as of March 6, 2005 (the "AGREEMENT"), by and between HIBERNIA CORPORATION, a Louisiana corporation ("HIBERNIA"), and CAPITAL ONE...Agreement and Plan of Merger • September 8th, 2005 • Hibernia Corp • National commercial banks • New York
