The original "The Little Mermaid" story by Hans Christian Andersen?

Okay, I was reading the original story of "The Little Mermaid" by Hans Christian Andersen, and in the story, it said, "..the old lady ordered eight great oysters to attach themselves to the tail of the princess to show her high rank." So i was hoping someone knew what that meant, like where would the oysters attach themselves? Or is it another way of saying the little mermaid has oyster pearls somewhere on her tail. Even so, does anyone know where they would go? I mean, I know it's just a story, but I'm having a very hard time painting that mental picture, and it's driving me nuts. Can someone help me?