<Question, I can't find these specimens in my limited shell references, are there common names associated with the shells in question? Thanks, Michael> Michael, both shells are slit shells - that's the common name of the family. I don't think most of the slit shells are sufficiently widely known to have generally accepted common names. Based on scientific name and place of origin, Pleurotomaria westralis might be called the western slit shell or the Australian slit shell. P. tangaroana might be called the Tangaroa slit shell or the New Zealand slit shell. However, these names do not have widespread general acceptance like map cowrie or bat volute. Paul M. Rhode Island