Png yellow thistle flowers vintage sketch https://www.rawpixel.com/image/2611552/free-illustration-png-herbal-medical-botany-holy-thistleView licenseA blessed thistle (Cnicus palustris) with an associated insect and its anatomical segments. Coloured etching, c. 1830. https://www.rawpixel.com/image/13981746/image-paper-butterfly-flowerFree Image from public domain license