Jennifer,
I have used a small X-ray machine to study shell thickness in
Littorinidae shells ("winkles").
 
Regards,
Bill P.
 
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* Charles (Bill) Pettitt           *     Keeper of Invertebrates     *
*                                  *      (& network supervisor)     *
* E-mail: [log in to unmask]      *     Manchester Museum           *
*                                  *     University of Manchester    *
* Tel: +44.61.275.2666             *     Manchester  M13 9PL         *
* Fax: +44.61.275.2676             *     United Kingdom              *
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