Michaux remarks that he is unable to give any reason why the names of Sour gum, Black gum, etc., have been bestowed upon these trees, as they spontaneously exude no sap or fluid which could give rise to such an appellation. We suspect that the term has arisen from a comparison of the autumnal tints of these trees belonging to the genus Nyssa, with those of the Sweet gum or Liquidambar, which, at a short distance, they so much resemble in the early autumn.