Retina of the eye (100X)
The picture mostly speak for itself, but as you can see the retina consists of many layers. The photosensitive cells, the rods and cones, are situated close to the choroid at the bottom of all these layers. The layers above the rods and cones are comprised of alternating layers of nerve fibers and their nuclei (dark layers = nuclei, light layers = axons and dendrites). You might've already found out that the light actually passes through all these layers to reach the rods and cones. You're actually looking through all these cells as you're reading this. Isn't that cool?