Dear Conch-L the link is a picture of an operculum http://www.ganvana.com/UploadFiles/picone/20130327.jpg My question is: Can we find the age of a shell by counting the rings on it's operculum ? is the rings a kind of dendrochronology? Best Regards He Jing ---------------------------------------------------------------------- [log in to unmask] - a forum for informal discussions on molluscs To leave this list, click on the following web link: http://listserv.uga.edu/cgi-bin/wa?SUBED1=conch-l&A=1 Type your email address and name in the appropriate box and click leave the list. ----------------------------------------------------------------------