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.