For many years palæontologists have anxiously awaited the reconstruction of the complete skeleton of Diprotodon by Dr. E. C. Stirling, Mr. Zietz, and their colleagues in the South Australian Museum. In 1893, when it was announced that numerous nearly complete skeletons of this gigantic extinct marsupial had been discovered in the arid interior of South Australia, it was hoped that all details of its osteology would soon be known; but the difficulties of excavating and transporting the fragile bones, and the skill and patience needed in preparing them after they reached the Museum in Adelaide, were so considerable as to necessitate long delay in obtaining satisfactory results. At last, however, a mounted reproduction of a skeleton has been completed in plaster, and Dr. Stirling has published three excellent photographs of the specimen in the “Report of the Board of Governors of the Public Library, Museum, and Art Gallery of South Australia for 1905–6,” lately received. The Governors of the South Australian Museum have given a copy of this restoration to the University of Cambridge, where it is now mounted in the Museum of Zoology. They have also generously presented to the British Museum a set of actual limb-bones and caudal vertebræ, with sufficient plaster casts to complete the reconstructed skeleton which is shown in Plate XV. As this restoration differs in some respects from that in Adelaide, it appears to need a brief explanation.