Abstract Smith Woodward embarked on the production of a catalogue of fossil fishes half a century after Louis Agassiz began a similar exercise. These two palaeontological goliaths remain the only authorities who saw all relevant fossil fish material in all important collections. Between their works there was a substantial increase in the number of species recognized, reflecting the nineteenth-century passion for collecting, the rise of museums, as well as an acceptance that species change through time. Agassiz was working in pre-evolutionary days but Smith Woodward’s view on fish diversity was strongly influenced by the theory of evolution and specifically the writings of Thomas Henry Huxley as well as those of Edward Drinker Cope and Ramsay Heatley Traquair and their ideas of grades of evolution. Many of Smith Woodward’s generic and species descriptions survive today as his lasting legacy. Higher classification has changed considerably with new discoveries and differing methods of classification.