The inner bark of the root of Juglans cinerea, collected in autumn.

Characters. - In flat or curved pieces, from an eighth to a quarter of an inch (3 to 6 millimetres) thick; the outer surface nearly free from soft cork; deep brown; the inner surface smooth and striate; transverse fracture short, delicately checkered, whitish and brown; odour feeble; taste bitter and somewhat acrid.

Uses. - It is a mild cathartic, especially useful in the treatment of chronic constipation, dysentery and congestion of the abdominal viscera. It has a slight action as a hepatic stimulant (p. 403), and is useful in malarial conditions (pp. 375 and 407).