This is a really neat picture. What you are looking at is the layer of skin cells of Frontenac grapes under a fluorescence microscope. What makes it even more interesting is that this is the grape during véraison. The top picture is a green grape, where you can see the anthocyanins forming in the skin. The bottom picture is a grape where the skin has already changed color, but the pulp is still clear. The first few layers of cells under the pulp are showing some color, however there aren’t any anthocyanic vacuolar inclusions in the pulp cells. Pretty interesting, huh?