Editing Seashell (section)

=== Polyplacophorans ===
{{main|Chiton}}
[[File:Chiton tuberculatus plates.jpg|thumb|130px|left|Loose valves or plates from ''[[Chiton tuberculatus]]'' from the beachdrift on the southeast coast of [[Nevis]], [[West Indies]]]]
[[Chiton]] plates or valves often wash up on beaches in rocky areas where chitons are common. Chiton shells, which are composed of eight separate plates and a girdle, usually come apart not long after death, so they are almost always found as disarticulated plates. Plates from larger species of chitons are sometimes known as "butterfly shells" because of their shape.