clover fern: any of several water ferns of the genus Marsilea having four leaflets
fern: any of numerous flowerless and seedless vascular plants having true roots from a rhizome and fronds that uncurl upward; reproduce by spores
butterwort: any of numerous carnivorous bog plants of the genus Pinguicula having showy purple or yellow or white flowers and a rosette of basal leaves coated with a sticky secretion to trap small insects