This section is from the book "Handbook Of Hardy Trees, Shrubs, And Herbaceous Plants", by W. Botting Hemsley. Also available from Amazon: Handbook of hardy trees, shrubs, and herbaceous plants.
Shrubs with imparipinnate leaves and yellow or reddish flowers in axillary racemes. The stipitate membranaceous inflated pod is the main character of the genus. There are about seven or eight species, from the Mediterranean region and tropical Asia. The name is from which was given to a plant by the ancients.
1. C. arborescens. Bladder Senna.- This is the only species familiar in gardens, having yellow flowers and bladder-like pods. It is a native of the South of Europe.