Help needed to ID shells from Turks Islands

[paul monfils]

These are shell plates of chitons.  I can't name the species from this picture, but chitons are a separate class of mollusks, which have a shell made up of 8 overlapping plates held together by a muscular band around the outer edge, called the girdle.  They live attached to rocks and other hard surfaces.  When they die, the girdle and soft parts decompose, allowing the individual shell plates to scatter and be washed ashore. Here are a few pictures of living chitons:

http://www.everystockphoto.com/photo.php...Id=5967637
http://epod.usra.edu/blog/2005/07/chiton...rmuda.html
http://www.treknature.com/gallery/photo200627.htm


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