Since the establishment of the genus Ectatorhinus by Lacordaire ¹) for a beautiful species of Rhynchophorous beetles discovered in the island of Borneo by the celebrated naturalist R. Wallace, two other species have been described by Mr. F. Pascoe ²) viz: E. Adamsi of Japan and E. femoratus of Sarawak (Borneo). The entomological collections brought home by the Dutch Scientific Expedition to central Sumatra, contain a unique female specimen of a new species of which I possess also a single specimen of the other sex, captured at Malacca by the Comte de Castelneau.