It's the one with the little blond haired girl (naked) staring into the pond.

She's lost something important in that pool - it's a transformation story - and she stares into it until she becomes a woman and finally turns into what is known as "cotton grass" which is a coarse grass with pretty tufty blond tops when it blooms. I have some in a few spots in my shady woodland gardens :) It's a gorgeous story - you should really try and find it! I need to hunt it down again, I should have the book in my collection and don't!