Illustration of a giraffe from Dictionnaire des Sciences Naturelles by Pierre Jean Francois Turpin (1840). Digitally enhanced… Free Image from public domain license 
Different types of birds illustrated by Charles Dessalines D' Orbigny (1806-1876) Digitally enhanced from our own 1892… Free Image from public domain license 
Different types of birds illustrated by Charles Dessalines D' Orbigny (1806-1876). Digitally enhanced from our own 1892… Free Image from public domain license 
Red-cheeked Cordonbleu (Uraeginthus Bengalus) and Java Sparrow (Lonchura Oryzivora) illustrated by Charles Dessalines D'… Free Image from public domain license 
Different types of birds illustrated by Charles Dessalines D' Orbigny (1806-1876) Digitally enhanced from our own 1892… Free Image from public domain license 
Different types of birds illustrated by Charles Dessalines D' Orbigny (1806-1876) Digitally enhanced from our own 1892… Free Image from public domain license 
King vulture (Sarcoramphus papa) illustrated by Charles Dessalines D' Orbigny (1806-1876). Digitally enhanced from our own… Free Image from public domain license 
Different types of birds illustrated by Charles Dessalines D' Orbigny (1806-1876) Digitally enhanced from our own 1892… Free Image from public domain license 
Struthio (Autruche de lancien continent) illustrated by Charles Dessalines D' Orbigny (1806-1876). Digitally enhanced from… Free Image from public domain license 
Different types of butterfly illustrated by Charles Dessalines D' Orbigny (1806-1876). Digitally enhanced from our own 1892… Free Image from public domain license 
Purple heron (Ardea purpurea) illustrated by Charles Dessalines D' Orbigny (1806-1876). Digitally enhanced from our own 1892… Free Image from public domain license 
Different types of birds illustrated by Charles Dessalines D' Orbigny (1806-1876) Digitally enhanced from our own 1892… Free Image from public domain license 
Pavonine quetzal (Pharomachrus pavoninus) illustrated by Charles Dessalines D' Orbigny (1806-1876). Digitally enhanced from… Free Image from public domain license 
Different types of birds illustrated by Charles Dessalines D' Orbigny (1806-1876). Digitally enhanced from our own 1892… Free Image from public domain license 
Different types of birds illustrated by Charles Dessalines D' Orbigny (1806-1876) Digitally enhanced from our own 1892… Free Image from public domain license 
Different types of birds illustrated by Charles Dessalines D' Orbigny (1806-1876) Digitally enhanced from our own 1892… Free Image from public domain license 
Different types of mollusks illustrated by Charles Dessalines D' Orbigny (1806-1876). Digitally enhanced from our own 1892… Free Image from public domain license 
Different types of moths illustrated by Charles Dessalines D' Orbigny (1806-1876). Digitally enhanced from our own 1892… Free Image from public domain license 
Different types of mollusks illustrated by Charles Dessalines D' Orbigny (1806-1876). Digitally enhanced from our own 1892… Free Image from public domain license 
Collection of butterflies illustrated by Charles Dessalines D' Orbigny (1806-1876). Digitally enhanced from our own 1892… Free Image from public domain license 
Red-tailed Finch (Estrelda ruficauda) illustrated by Elizabeth Gould (1804–1841) for John Gould’s (1804-1881)… Free Image from public domain license 
Banded Grass Finch (Poephila cincta) illustrated by Elizabeth Gould (1804–1841) for John Gould’s (1804-1881)… Free Image from public domain license 
Shining starling (Aplonis metallica) illustrated by Elizabeth Gould (1804–1841) for John Gould’s (1804-1881)… Free Image from public domain license 
Great-billed Gerygone (Gerygone magnirostris) illustrated by Elizabeth Gould (1804–1841) for John Gould’s (1804… Free Image from public domain license 
Study of three feathers (1813–1838) by Dirk Salm. Original from The Rijksmuseum. Digitally enhanced by rawpixel. Free Image from public domain license 
Dog's head (1920) by Julie de Graag (1877-1924). Original from The Rijksmuseum. Digitally enhanced by rawpixel. Free Image from public domain license