> about 5-6mm the muricid had to bore. Patience pays off! (and the > only > large muricids in most of these localities are Typhis, so I guess > these must be the culprits). Of course molluscs with shells are not the only molluscs which bore holes in shells. From what I have seen modern day octopus make small cylindrical holes in the spires of univalves. Perhaps there was an extinct species of octopus or something else that was responsible. Andrew D