Sept. 27, 1961 - The First Lady will present the new President's Cup in a special open-jumper class at the Washington National Horse Show in October. The White House made the announcement today. The show will be held at the National Guard Armory Oct. 24 to 29. A special Presidential box will be set up on the arena sidelines. The President may attend. Mrs. Kennedy will view the finals of the event. She is known for her interest in horses and riding.