There has been recent mention lately about the mantle papillae
corresponding in position with the spots on spotted shells.  This has
been mentioned in the past, and in some cases you can note correlation
of papillae and shell surface spots.

To understand the relationship, you need to know about how the color
pattern is applied.  Does the mantle deposit the color pattern with the
mantle fully extended, all the surface being deposited at once?  If so,
this would perhaps make a relationship of shell spots and papillae.  How
long would it take for the mantle to deposit the color pattern?  If the
mantle moved slightly, the spots would be blurred like double exposed
film.  Cyp. rashleighana were observed to progress from a "bulla" stage
to adult in about a week, with the shell wall still thin.

Other gastropods and bivalves add to the outer lip only.  How is the
color pattern (spots primarily) produced?
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                     Aloha from Wesley M. Thorsson
Editor of Internet Hawaiian Shell News, a monthly Internet Publication
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