There are a few things to point out in this picture, first thing, depth of field, this picture makes the mushroom the main focus, whilst the background is blurred. Also, we can see the texture inside of the mushroom. I like this picture the most it is zoomed in, and the texture is smooth.
Arthur Rackham - Peter Pan in Kensington Gardens was originally part of an earlier work, The Little White Bird by J.M. Barrie. The Peter Pan chapters were extracted and published as a separate work in 1906. The color plates to Peter Pan in Kensington Gardens by Arthur Rackham made the book immediately popular, and drew attention to Rackham, who was not well-known before then.