Cassia senna  var. senna  shows considerable morphological <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

variations though    the cytogenetical studies of C. acutifolia  and C. angustifolia exhibit very close relationship.

The method of drying   affects the percentage of sennosides in the leaflets: sun-drying sennosides, 2.98; moisture, 70.60%; and oven-drying (40°± 2°)   sennosides, 3.03; moisture, 72.80%.

Arabian samples of senna have been found mixed with stems, midribs,    dirt and the leaflets and pods of Cassia auriculata  and C.    holosericia  Fresen., reported to have been introduced into <?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" />India,    C. italica  and C montana ; the mature leaves of C. tora  are   also sometimes used as adulterants. Others are Ailanthus altissima    (Mill.) Swingle, Colutea arborescens  Linn. and Globularia alypum    Linn. The leaflets of Coriaria myrtifolia  Linn., Solenostemma    argel  Hayne, Tephrosia apollinea  DC. and T. purpurea  Pers.    have been detected in commercial samples, and reported to be    poisonous.