Seven alkaloids have been isolated from Lycopodium paniculatum Desvaux. Three of these, lycopodine, dihydrolycopodine, and acetyldihydrolycopodine are alkaloids of established structure. Of the four new alkaloids the structure of one, paniculatine, has been clarified. Its structure, elucidated through an X-ray crystallographic study of its hydrobromide, is different from other alkaloids of the Lycopodium family. The spectral properties of paniculatine are interpreted in the light of its structure.