Here are the reliminary drawings for Edward Lear's book ''Illustrations of the family of Psittacidae, or parrots: the greater part of them species hitherto unfigured, containing forty-two lithographic plates, drawn from life, and on stone' 1832 You can see the final plates here.
Edward Lear was TWENTY YEARS OLD when his Parrot book was published!!
Edward Lear Sketches of Parrots Relating to 'Illustrations of the Family of Psittacidae, or Parrots' (1832), ca. 1830 (MS Typ 55.9). Houghton Library, Harvard University.