American botanist (1844-1868).
Horace Mann Jr. (February 25, 1844 – November 11, 1868) was an American botanist, son of Horace Mann. His mother was one of the famous Peabody Sisters Mary Tyler Peabody Mann. Mentored in botany by Henry David Thoreau, whom he accompanied on an expedition to Minnesota, Mann took classes in zoology with Louis Agassiz and assisted William Tufts Brigham on a botanical survey of the Hawaiian Islands. Mann was to have headed the botanical garden at Harvard, but died of tuberculosis at age twenty-four. His own herbarium was purchased by Cornell University and became the basis of that university's co