Occasionally I find a shark tooth that is so nasty looking that rather than leaving it lying on the beach, I pick it up and take it home for further inspection. Usually the "nasty" looking tooth is a tiger shark, hemi, mako, or maybe even a small Meg. Years ago I heard someone refer to a tooth at one of our club meetings as a "digested" tooth, one that had been swallowed by the shark, "nastified" by its stomach acids, and exited later on perhaps not looking as nice as when it was swallowed. I