Ranunculus (buttercups, spearworts, water crowfoots, lesser celandine)
They are mostly herbaceous perennials with bright yellow or white flowers (if white, still with a yellow centre); some areannuals or biennials. A few species have orange or red flowers. The name Ranunculus is Late Latin for "little frog," from rana "frog" and a diminutive ending. This probably refers to many species being found near water, like frogs.The name buttercup may derive from a false belief that the plants give butter its characteristic yellow hue (in fact it is poisonous to cows and other livestock). A popular children's game involves holding a buttercup up to the chin; a yellow reflection is supposed to indicate fondness for butter.