THE FRUITS OF JASMINUM-MESNYI (OLEACEAE), AND THE DISTINCTION BETWEENJASMINUM AND MENODORA

The fruit and seed morphology and anatomy of Jasminum mesnyi are descr ibed here for the first time. as part of a larger comparative study on the fruit and seed structures in the Oleaceae. The evidence presented here weakens the current delimitation between Jasminum and Menodora. As usual in Jasminum, the two carpels of the ovary of J. mesnyi grow u p independently to form separate mericarps, while the septum remains s mall. At maturity, however, the mericarps dry out and dehisce loculici dally on their adaxial side, from the style outward. The wall of the m ericarps is membranous at their distal ends, but increasingly thickene d toward the base. This is unique in Jasminum but reminiscent of Menod ora, where the mericarps of most species show circumscissile dehiscenc e. The seed coat of Jasminum mesnyi is as unequal-sided as in Jasminum nudiflorum, which in turn shares dry, irregularly fragmenting mericar ps with Menodora spinescens. After a discussion of the characters supp osed to separate the two genera, it is concluded that the discontinuit y between them is not greater than among some of the sections of Jasmi num. A decision on the final status of these taxa is deferred until de tailed molecular evidence becomes available.