A detailed study of the basic components of the roots of Aconitum heterophyllum has led to the isolation of seven new diterpene alkaloids. The weak base fraction yielded besides heteratisine, three more alkaloids designated as heterophyllisine, heterophylline, and heterophyllidine. These compounds are lactone alkaloids which are structurally related to heteratisine. The strong base fraction yielded besides atisine two new alkaloids, atidine and F-dihydroatisine, the latter previously encountered as a reduction product of atisine and isoatisine. The very strong base fraction yielded in addition to hetisine, alkaloids designated as hetidine and hetisinone. The latter had been encountered previously as a chemical transformation product of hetisine. © 1968.