SINCE Sir George Grey sent the three original specimens to the British Museum, in 1843, this interesting marsupial, one of the ‘Rat-Kangaroos’ of the subfamily Potoroinse, has been completely lost to science. There is a somewhat doubtful record of it in 1878, but no specimen of the animal exists in any museum in Australia, and there was much to justify the generally accepted view that the animal was extinct.