Reduction of Placolobium Mig. to Ormosia Jackson (Leg.-Pap.)

At the request of Mr Airy Shaw the type specimen of Placolobium sumatranum Miq. Fl. Ind. Bat. 1, 1 (1855) 1082 has been examined from the Herbarium at Utrecht by kind permission of Prof. Lanjouw. It is very scrappy and consists of a loose rachis and leaflets and unfortunately the fruit valves described by Miquel are not present and could not be found among the carpologica by Miss Mennega. A close examination of the specimen has, however, shown that exactly similar specimens are found under Ormosia macrodisca Baker, showing the slightly sunken veins, areolae of similar size, epidermis with slightly granular surface and same colour, leaflets of same texture, and petiolules thickened, wrinkled transversely with shallow grooves. Moreover, the rachis also fits exactly that of O. macrodisca, is of the same size, lengthwise ribbed, and with the blackish trichomes at the nodes. From the description the fruit valves must also be similar to those of Ormosia macrodisca. Obviously Miquel had received leaves of a sterile twig and a loose fruit (without seed) picked from the ground. At that time the species was undescribed and he was unaware that such large woody fruits occurred in the genus. The species is rather widely distributed and several later collections have been made in Central Sumatra according to Mrs. Knaap in Reinwardtia 6 (1962) 230.