The leaves of a Glochidion species, probably Glochidion philippicum (Cav.) C. B. Rob., of the family Euphorbiaceae, contain three new interrelated imidazole alkaloids, glochidine (I), glochidicine (II), and Nα-4′-oxodecanoylhistamine (III), together with the known alkaloid Nα-cinnamoylhistamine. The bark of this species contains only glochidicine and Nα-cinnamoylhistamine. © 1967 CSIRO. All rights reserved.