1. East Indian tree having long pods containing a black cathartic pulp used as a horse medicine
   - horse cassia, Cassia marginata

Type of: cassia

• genus Pyxidanthera
• genus Quamassia
• genus Quassia
• genus Quercus
• genus Quiscalus
• genus Rachycentron
• genus Radiigera
• genus Radyera
• genus Raffia
• genus Raja
• genus Ramalina
• genus Ramphomicron
• genus Rana
• genus Ranatra
• genus Rangifer
• genus Ranunculus
• genus Raoulia
• genus Raphanus
• genus Raphia
• genus Raphicerus
• genus Raphus
• genus Ratibida
• genus Rattus
• genus Rauvolfia
• genus Rauwolfia