ABSTRACT Five years before the discovery in 1865 of Dodo Raphus cucullatus fossil remains at the Mare aux Songes, Mauritius, local physician Philip Ayres had inadvertently unearthed a fragmented dodo bone from an unknown cave in the Black River District, south of the capital Port Louis. The bone got muddled with fossil material from the dodo’s closest relative, the Solitaire Pezophaps solitaria, before being sent to comparative anatomist Richard Owen at the then British Museum. Denied access by Owen to these specimens when compiling data for their Solitaire osteological monograph, comparative anatomist Alfred Newton and his brother Edward were understandably enraged, which resulted in some bad-tempered correspondence between them and Owen. Rather, inexplicably, Owen never scientifically described the Ayres dodo bone, now ignored for over 170 years, and its identification to element type is still in doubt. Here, I describe the probable cave in which this Dodo fossil was discovered, its true identification, the correspondence between Ayres, the Newton brothers and Owen, and the likely reasons why Owen did not follow up Ayres’s discovery.