Gentian (Gentiana holopetala) (1936) by Mary Vaux Walcott. Original from The Smithsonian. Digitally enhanced by rawpixel.
https://www.rawpixel.com/image/2613496/free-illustration-image-flower-wildflowers-hand-drawn-vintage-purple-watercolorFree Image from public domain license
Bitter root (Gentiana lutea) illustration. Digitally enhanced from our own book, Medical Botany (1836) by John Stephenson…
https://www.rawpixel.com/image/327107/free-illustration-image-bitter-root-flowers-public-domain-yellow-flower-watercolorFree Image from public domain license
Flower psd vintage botanical illustration set, remixed from artworks by Pierre-Joseph Redouté