DIEFFENBACHIA, dēf-fĕn-băk'ĭ-ạ, a genus of Araceæ (arum family), of which there are about 15 species, found in the woods of South America and the West Indies. Their leaves have sheathing petioles, and are often variegated. Their form of inflorescence is the spathe-enclosed spadix characteristic of the order, the spathe in Dieffenbachia being green or yellowish. The best-known species is the poisonous dumb cane of the West Indies (D. seguin).