Three new alkaloids, quadrigemine C [1], isopsychotridine B [2], and iso-psychotridine A [31, have been isolated from Psychotria olmdes, in addition to the known psychotridine {4} and hodgkinsine [5]. Their structures were determined from spectral data. The stem bark of Calycodendron milnei contains hodgkinsine [5] and calycosidine, a new structurally related alkaloid. © 1987, American Chemical Society. All rights reserved.