In the rich collection of Red-Crag fossils gathered together during the course of many years in the neighbourhood of Waldringfield by the Rev. H. Canham, now through the joint liberality of Sir Richard Wallace and Mr. Canham located in the Ipswich Museum, is a very perfect mammalian tooth, which has been placed in my hands for identification. It proves to be the right upper first true molar of an animal of the genus Hyænarctos of Falconer & Cautley. In the Quarterly Journal of the Geological Society, vol. xxxiii. No. 129 (Feb. 1, 1877), at p. 133, it is recorded that, at the meeting of the Society held on November 22, 1876, “Mr. Charlesworth stated that he had obtained from the Crag a tooth which had been pronounced by Mr. W. Davies, of the British Museum, to come nearest to that of Hyænarctos among known Mammalia.” The tooth referred to by Mr. Charlesworth is now in the collection of Mr. William Reed, M.R.C.S., of York, who has obligingly sent it to me for exhibition to the Society. It is the corresponding upper molar of the opposite side, and so like that of Mr. Canham's collection that, except for being perfectly unworn, it might almost have belonged to the same individual.