Delstaphigine (1) and 14-O-benzoyldelphonine (2), two new C19-diterpenoid alkaloids, and chasmaconitine (4) have been isolated from the seeds of Delphinium staphisagria. The structures of these alkaloids were determined from spectral data and by correlation with alkaloids of established structures. Thus methylation of delstaphigine (1) afforded delphinine (3). 14-O-Benzoyldelphonine (2) was synthesized from both delphinine (3) and delphonine (5). Chasmaconitine (4) has not been previously isolated from a Delphinium species.