A base, now named bicuculline, previously isolated fromDicentra cucullariaand referred to as alkaloid α has been obtained fromCorydalis sempervirensandAdlumia fungosa. A chemical examination of this alkaloid has disclosed an exceptionally close relation to hydrastine, from which it differs only by the substitution of a methylenedioxy group for the two methoxyl groups. Accordingly, hydrolytic oxidation yields hydrastinine and 2-carboxy-3:4-methylenedioxy-benzaldehyde, which on reduction is converted into the known 3:4-methylenedioxy-phthalide.