A lock of hair and wool leggings belonging to Sitting Bull, below, leader of the Hunkpapa Lakota Sioux, are to be returned by the Smithsonian’s National Museum of Natural History to his closest living relatives. In an announcement yesterday, the museum said that after Sitting Bull was killed in 1890 while being arrested by tribal police, his body was in temporary possession of Horace Deeble, an Army doctor at the Fort Yates military post in North Dakota, who obtained the hair and leggings from the body and sent them to the museum in 1896. The return of the hair and leggings was requested by Ernie LaPointe, Sitting Bull’s great-grandson and a representative of the four known living great-grandchildren.