As a result of the present investigation, two new alkaloids have been added to the small number of such compounds which are known to occur in plants belonging to the N.O. Compositæ. The names senecifoline and senecifolidine are proposed for these alkaloids, and the formulæ C18H 27O8N and C18H25O7N respectively assigned to them; thus it appears that the two substances differ by the elements of a molecule of water. Senecifoline has been hydrolysed by alkalis into a dibasic acid, C10H16O6, for which the name senecifolic acid is suggested, and a base, C8H 11O2N, which it is proposed to term senecifolinine. The free base was not isolated. From a consideration of the products of this action, it would appear that the reaction may be represented by the following equation: C18H27O8N + 2NaOH = C10H 14O6Na2 + C8H11O 2N + 2H2O, which is analogous to the decomposition of atropine into atropic acid and tropine by means of barium hydroxide: 2C 17H23O3N + Ba(OH)2 = (C 9H7O2)2Ba + 2C8H 15ON + 2H2O.