Mists and mellow fruitfulness?!

The diary tells me it's November, NaNoWriMo means it definitely is November but nature in these parts seems a little confused! Walking my dog in the woods this morning I came across catkins dancing on birch branches a couple of months ahead of their usual time, and in the garden, almost buried beneath the mounds of fallen leaves I must clear up today, my primrose was in full bloom. It reminded me of a lovely story I once read as a child about the seasons swapping their characteristics with each other and the world getting into a real muddle - who it was by or what it was called I can't recall. I wonder if anyone else remembers it?