Ray and Willughby were the first ornithologists to discard the Aristotelian principles of classification by function, replacing them with a morphological system based on beak form, foot structure and body size that reflected the true relationships even better than Linnaeus's Systema naturae of sixty years later. The credit for this system almost certainly belongs to Ray, who edited and supplemented the Ornithologiae from notes left at Willughby's death, and who, during their years of partnership, had done the major part of the observations and records. In an attempt to bring order out of the chaos of tradition, Ray collated his and Willughby's observations against those recorded by all previous writers, eliminating duplicate species, species vaguely described or reported on hearsay, and species that were clearly fabulous. Revised English translation by Ray with the addition of 3 treatises on fowling, the care of songbirds, and falconry, London, 1678. Digital facsimile of the 1678 edition from the Biodiversity Heritage Library at this link.

A large folio volume with 187 engraved plates considered the first modern encyclopedia on fish, this was largely the work of John Ray, prepared and expanded from Willougby's notes, more than a decade after his death. The work was published by the Royal Society at considerable expense; the Society's President, Samuel Pepys, personally underwrote 79 of the engraved plates, and other members sponsored the remaining plates. Despite its importance and sumptuous production, the work was slow to sell, and the Society, still owning a large number of copies 50 years after publication, authorized a re-issue of the original sheets with a cancel title in 1743..

This is the second and best edition in 2 volumes of works that were first issued separately in 1673 and 1693 respectively. For Rauwolf see No. 7327. Digital facsimile of the 1738 edition from the Medical Heritage Library, Internet Archive, at this link.