Siskin ( Spinus spinus) 1♂ 2♀ illustrated by the von Wright brothers. Digitally enhanced from our own 1929 folio version of… https://www.rawpixel.com/image/326193/free-illustration-image-von-wright-brothers-spinus-spinus-birdFree Image from public domain licenseSiskin 2♀ (Spinus spinus) illustrated by the von Wright brothers. Digitally enhanced from our own 1929 folio version of… https://www.rawpixel.com/image/326299/premium-illustration-psd-von-wright-spinus-spinus-abstractView licenseAmerican Goldfinch from Birds of America (1827) by John James Audubon, etched by William Home Lizars. Original from… https://www.rawpixel.com/image/277440/free-illustration-image-audubon-goldfinch-birds-america-public-domainFree Image from public domain licensePine Finch from Birds of America (1827) by John James Audubon, etched by William Home Lizars. Original from University of… https://www.rawpixel.com/image/277467/free-illustration-image-audubon-pine-birds-america-public-domainFree Image from public domain licenseSiskin 1♂ (Spinus spinus) illustrated by the von Wright brothers. Digitally enhanced from our own 1929 folio version of… https://www.rawpixel.com/image/326298/premium-illustration-psd-von-wright-brothers-spinus-spinus-siskinView license