The bark of several species of
Cinnamomum grown in China, etc.; Chinese cinnamon. It is imported as
cassia, but commonly sold as cinnamon, from which it differs more or less in strength and flavor, and the amount of outer bark attached. [
1913 Webster]
" The medicinal “cassia” (Cassia pulp) is the laxative pulp of the pods of a leguminous tree (Cassia fistula or Pudding-pipe tree), native in the East Indies but naturalized in various tropical countries."
[1913 Webster]