Two new peptide ergot alkaloids have been found in saprophytic cultures of strain 231 F.I. of Claviceps purpurea which produces mainly ergotoxine. They belong to the groups of ergotoxine and ergoxine respectively and contain a-amino-butyric acid as the second amino acid of the side chain.Their structures have been assigned on the basis of spectral data, amino acidcomposition and degradation procedures. The names of ergobutyrine (II) and ergobutine (III) are proposed for them.