Sharp prickles on margins
Purple; flowerheads are subtended by an involucre with a clasping shape of a cup
- "Professor McGonagall […] was wearing dress robes of red tartan and had arranged a rather ugly wreath of thistles around the brim of her hat […]."
A thistle is a flowering plant characterised by leaves with sharp prickles on the margins and, often, with prickles on surfaces such as the stem and flat parts of leaves. Thistle is the floral emblem of Scotland.