Some time ago Mr. J. van Rijn van Alkemade, the Hague, presented to the Rijksmuseum van Natuurlijke Historie a most remarkable double tusk of a Sumatran elephant. Mr. Van Rijn van Alkemade could provide us with the following particulars about the specimen. It was shot in the residency of Palembang before 1906 and the above mentioned double tusk was presented to his father at that time Resident of Palembang. The elephant was a four tusker, the other double tusk, which was of a corresponding shape as the one presented to the Museum, came into the hands of a Chinese dealer. Double tusks in elephants are reported in more than one occasion and it is also a known fact that sometimes twisted tusks in elephants can occur (cf. Colyer: Variations and diseases of the teeth of animals, 1936, pp. 548—551). As far as I am aware a double tusk of which one is about straight, the other twisted around the first has never been reported till now. The tusks have been cut off and, unfortunate enough, the skull has not been preserved, therefore the situtation "in facto" is unknown and every comment upon how these teeth originated must remain speculative. As the first winding of the spiral tusk passes on the right side of the normal one and the tip of the former is damaged on the same side it is not unlikely that we have the rightsided pair before us. As said above one of the tusks is nearly straight, though it shows at its basal part a slightly upwards directed curve as to give place to the twisted tusk to pass underneath of it. The distal part bends slightly upwards as in normal tusks. The length measured in straight line is 87 cm, height at base 5.5 cm, breadth at base 6.5 cm. The spiral tusk has a length in straight