Turkish Roenzeria hybrid produces ten proaporphine-tryptamine dimers, two of which, (-hroehybridine [l] and (-hroerneridine [8], were previously known. The dimers have been divided into three subgroups based on the stereochemistry at C-9 and at the spiro C-10 center. The first subgroup, syn 9-OMe axial, includes (-)-roehybridine [l], (-)-norroehybridine [2], (-)-0-methylroehybridine [3], (-broehybridine p-N-oxide [4], and (-) roehybramine [SI. The second subgroup, syn 9-OMe equatorial, has only two members, (+) roehymine [6] and (+)-roebramine [T. The third subgroup, anti 9-OMe axial, includes (-) roemeridine 181, (-)-0-methylroemeridine [9], and (-)-roemebramine [lo]. In the syn series, A, the proaporphine nitrogen atom and the non-basic nitrogen of the indole moiety are on the same side of ring D, whereas they are on opposite sides in the anti series, B. The proaporphine-tryptamine dimers are a recently recognized group of heptacyclic alkaloids most probably formed biogenetically by Mannich-type condensation of a ketonic tetrahydroproaporphine with a tryptamine analogue. Prior to the present work, only two of these dimers had been known, namely (-)-roehybridine El] and (-) roemeridine [S} (1,2), and structures had been proposed for them (3,4). The purpose of the present paper is to describe eight additional proaporphine-tryptamine dimers and to reconsider some of the previously made structural and 'H-nmr spectral assignments.