by Scott Yanow   One of the early classic blues singers, Rosa Henderson (no relation to Fletcher or Horace Henderson) first began singing professionally in 1913 with her uncles carnival troupe. She was based in Texas until 1918 when she married Slim Henderson and began touring with the Mason Henderson Show. She primarily spent the 1920s performing in musical comedies in New York. Henderson, who began recording in 1923, sometimes used such pseudonyms as Flora Dale, Mamie Harris, Rosa Green, Sarah Johnson, Sally Ritz, Bessie Williams, Josephine Thomas and Gladys White on her records! In the late 1920s she started gradually dropping out of the music scene although she continued performing now and then into the mid-1930s. Henderson worked outside of music (including in a New York department store), but re-emerging as a singer for charity benefits as late as the 1960s. Rosa Henderson recorded 92 selections in all including 88 during 1923-27 and two apiece in 1928 and 1931; among her sidemen were Fletcher Henderson, Coleman Hawkins, Thomas Morris, Joe Smith, Cliff Jackson, Rex Stewart, Louis Metcalf, Fats Waller, and (on six numbers) James P. Johnson.