"It should not forgotten, however, that it was his "Observations on the natural history of the Cuckoo" (1788) that had won him membership in the Royal Society 10 years before. His work on bird migration, although done at about the same time, was not published until after his death in 1823. Both of these papers were landmarks in ornithological history, for no one prior to Jenner had approached these problems, of brood parasitism and migration, in anywhere near so comprehensive a fashion or with such searching questions."