CORRECTIONS

-- A Civil War quiz on the Schools & Learning page in the April 20 Metro section misstated the number of casualties in the Battle of Antietam. There were about 23,000 people killed, wounded or missing, not 23,000 dead.

-- An April 18 A-section article about Sarah Palin incorrectly said that the Alaska governor was traveling when she learned that her son Trig would have Down syndrome. Palin told an Evansville, Ind., audience that she was traveling when she discovered she was pregnant. She learned of the diagnosis weeks later.

-- An April 17 A-section item incorrectly described a former Illinois gubernatorial aide who pleaded not guilty in federal court. John Harris is a former chief of staff to ousted governor Rod Blagojevich but is not Blagojevich's most recent chief of staff.

-- A March 10 Metro article on a handgun lawsuit misstated the name of a list of handguns certified for registration in the District. The standard is the California Roster of Handguns Certified for Sale, also known as the California Roster of Handguns Determined Not to Be Unsafe.

-- A Nov. 19, 2008, Metro article incorrectly described the origin of Valenti House, a residential treatment program that is part of Woodley House. It was named for Mary Margaret Valenti, wife of the late Jack Valenti of the Motion Picture Association of America.

-- On the Commuter Page in the June 29, 2008, Metro section, a list of possible transit stops on the proposed Purple Line in Maryland failed to include Riverdale Park.

The Washington Post is committed to correcting errors that appear in the newspaper. Those interested in contacting the paper for that purpose can send an e-mail to corrections@washpost.com or call the main number, 202-334-6000, and ask to be connected to the desk involved -- National, Foreign, Metro, Style, Sports, Business or any of the weekly sections. In addition, the ombudsman's number is 202-334-7582.