Many thanks for the answers on this shell identity. I didn't expect replies so quickly. COA obviously has a wide range of expertise available. But I still don't understand why this snail evolved sections on its spire that can only harbour parasites or symbiotics (no way of cleaning out). There is no way that I can see that it evolved something to improve its life. ---------------------------------------------------------------------- [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. ----------------------------------------------------------------------