Perianth of tiny Pilea flowers consists of 4 tepals in staminate and 3 tepals in pistillate flowers shown here. Ripening achenes are still surrounded by these three tepals, of which one sometimes becomes larger than the other two, shaped like a tall pointed cap--hence the name Pilea (in Greek and Latin "pilos" and "pileus," respectively, meant "brimless felted cap"--the cap worn by workers and liberated slaves, later known as the Cap of Liberty, or Phrygian Cap). There are at least two good examples of this enlarged pilos-shaped tepal visible against tan background here. The name Pilea was coined and the genus described by the British botanist John Lindley in 1821, Pilea previously included in Urtica by Carl Linnaeus.