Our Uncle Abe would occasionally sponsor fishing trips for the employees of the Auburn Curtain company where our father worked. He would hire a large boat and crew for the day and would set sail for the ocean. One time someone caught a large codfish. We were amazed to see that inside the codfish's mouth was a crab. We were studying the fish, wondering how a fish could be kosher since it ate treif. Someone was holding up the fish and Gedaliah was studying it and pointing things out when the fish twisted around and bit Gedaliah's finger. I remember we were all quite frightened.
note* As I remember Aba telling it, he said he actually stuck his finger in through the gills and through the mouth - where it got bitten.