Berberixa, an alkaloid which receives its name from having been found in the oerberis vulgaris or common barberry, but which has been obtained from many other plants, among which are the columbo root, false columbo (coscinium), gold thread (coptis), yellow root (xanthorrhisa), yellow puccoon (hydrastis), and probably the prickly ash (xanthoxylum). Some of these vegetables, all of which have yellow root wood, were used by the Indians for dyeing. The alkaloid, having the formula C40H17 NO8, occurs in the form of minute yellow crystals, has a bitter taste, and forms difficultly soluble salts with hydrochloric and sulphuric acids, and a readily soluble acetate. The impure muriate is used by the eclectic practitioners under the name of hydrastin, and must not be confounded with the colorless alkaloid hydras-tia, also found in the hydrastis Canadensis. The effects of berberina are probably those of a pure bitter, though it is less employed in medicine, except in the form of the impure muriate just mentioned, than the drugs, especially columbo, which contain it.